Re-enable covr

[MichaelChirico]

Filing this as an earmark to make sure we get around to restoring code coverage tests (shut off in #6122).

Upstream, our report (r-lib/covr#567) seems to be shared by a few other packages & was traced back to possible being an R 4.4.0+ issue. Maybe we can restore running on R 4.3.x?

For now, while debugging a related issue (r-lib/covr#576), I managed to see some coverage stats for the first time in a while, dumping them here lest they go to waste.

``` '/usr/bin/gcov' '/home/michael/github/data.table/src/assign.gcno' '-p' '-o' \ '/home/michael/github/data.table/src'

File 'assign.c'
Lines executed:95.18% of 789
Creating 'assign.c.gcov'

Lines executed:95.18% of 789
'/usr/bin/gcov' '/home/michael/github/data.table/src/between.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'between.c'
Lines executed:97.35% of 113
Creating 'between.c.gcov'

Lines executed:97.35% of 113
'/usr/bin/gcov' '/home/michael/github/data.table/src/bmerge.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'bmerge.c'
Lines executed:95.76% of 236
Creating 'bmerge.c.gcov'

Lines executed:95.76% of 236
'/usr/bin/gcov' '/home/michael/github/data.table/src/chmatch.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'chmatch.c'
Lines executed:85.71% of 98
Creating 'chmatch.c.gcov'

Lines executed:85.71% of 98
'/usr/bin/gcov' '/home/michael/github/data.table/src/cj.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'cj.c'
Lines executed:100.00% of 58
Creating 'cj.c.gcov'

Lines executed:100.00% of 58
'/usr/bin/gcov' '/home/michael/github/data.table/src/coalesce.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'coalesce.c'
Lines executed:100.00% of 119
Creating 'coalesce.c.gcov'

Lines executed:100.00% of 119
'/usr/bin/gcov' '/home/michael/github/data.table/src/dogroups.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'dogroups.c'
Lines executed:96.22% of 344
Creating 'dogroups.c.gcov'

Lines executed:96.22% of 344
'/usr/bin/gcov' '/home/michael/github/data.table/src/fastmean.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'fastmean.c'
Lines executed:92.42% of 66
Creating 'fastmean.c.gcov'

Lines executed:92.42% of 66
'/usr/bin/gcov' '/home/michael/github/data.table/src/fcast.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'fcast.c'
Lines executed:100.00% of 77
Creating 'fcast.c.gcov'

Lines executed:100.00% of 77
'/usr/bin/gcov' '/home/michael/github/data.table/src/fifelse.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'fifelse.c'
Lines executed:100.00% of 282
Creating 'fifelse.c.gcov'

Lines executed:100.00% of 282
'/usr/bin/gcov' '/home/michael/github/data.table/src/fmelt.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'fmelt.c'
Lines executed:99.66% of 585
Creating 'fmelt.c.gcov'

Lines executed:99.66% of 585
'/usr/bin/gcov' '/home/michael/github/data.table/src/forder.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'forder.c'
Lines executed:90.94% of 982
Creating 'forder.c.gcov'

Lines executed:90.94% of 982
'/usr/bin/gcov' '/home/michael/github/data.table/src/frank.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'frank.c'
Lines executed:98.84% of 173
Creating 'frank.c.gcov'

Lines executed:98.84% of 173
'/usr/bin/gcov' '/home/michael/github/data.table/src/fread.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'fread.c'
Lines executed:98.26% of 1263
Creating 'fread.c.gcov'

Lines executed:98.26% of 1263
'/usr/bin/gcov' '/home/michael/github/data.table/src/freadR.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'freadR.c'
Lines executed:93.67% of 442
Creating 'freadR.c.gcov'

Lines executed:93.67% of 442
'/usr/bin/gcov' '/home/michael/github/data.table/src/froll.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'froll.c'
Lines executed:100.00% of 245
Creating 'froll.c.gcov'

Lines executed:100.00% of 245
'/usr/bin/gcov' '/home/michael/github/data.table/src/frolladaptive.gcno' '-p'
'-o' '/home/michael/github/data.table/src'

File 'frolladaptive.c'
Lines executed:87.14% of 140
Creating 'frolladaptive.c.gcov'

Lines executed:87.14% of 140
'/usr/bin/gcov' '/home/michael/github/data.table/src/frollR.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'frollR.c'
Lines executed:96.48% of 199
Creating 'frollR.c.gcov'

Lines executed:96.48% of 199
'/usr/bin/gcov' '/home/michael/github/data.table/src/fsort.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'fsort.c'
Lines executed:70.83% of 144
Creating 'fsort.c.gcov'

Lines executed:70.83% of 144
'/usr/bin/gcov' '/home/michael/github/data.table/src/fwrite.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'fwrite.c'
Lines executed:86.40% of 500
Creating 'fwrite.c.gcov'

Lines executed:86.40% of 500
'/usr/bin/gcov' '/home/michael/github/data.table/src/fwriteR.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'fwriteR.c'
Lines executed:98.86% of 175
Creating 'fwriteR.c.gcov'

Lines executed:98.86% of 175
'/usr/bin/gcov' '/home/michael/github/data.table/src/gsumm.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'gsumm.c'
Lines executed:97.82% of 595
Creating 'gsumm.c.gcov'

Lines executed:97.82% of 595
'/usr/bin/gcov' '/home/michael/github/data.table/src/idatetime.gcno' '-p'
'-o' '/home/michael/github/data.table/src'

File 'idatetime.c'
Lines executed:98.04% of 102
Creating 'idatetime.c.gcov'

Lines executed:98.04% of 102
'/usr/bin/gcov' '/home/michael/github/data.table/src/ijoin.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'ijoin.c'
Lines executed:92.46% of 517
Creating 'ijoin.c.gcov'

Lines executed:92.46% of 517
'/usr/bin/gcov' '/home/michael/github/data.table/src/init.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'init.c'
Lines executed:95.28% of 106
Creating 'init.c.gcov'

Lines executed:95.28% of 106
'/usr/bin/gcov' '/home/michael/github/data.table/src/inrange.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'inrange.c'
Lines executed:100.00% of 9
Creating 'inrange.c.gcov'

Lines executed:100.00% of 9
'/usr/bin/gcov' '/home/michael/github/data.table/src/nafill.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'nafill.c'
Lines executed:98.18% of 165
Creating 'nafill.c.gcov'

Lines executed:98.18% of 165
'/usr/bin/gcov' '/home/michael/github/data.table/src/negate.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'negate.c'
Lines executed:92.31% of 13
Creating 'negate.c.gcov'

Lines executed:92.31% of 13
'/usr/bin/gcov' '/home/michael/github/data.table/src/nqrecreateindices.gcno'
'-p' '-o' '/home/michael/github/data.table/src'

File 'nqrecreateindices.c'
Lines executed:100.00% of 24
Creating 'nqrecreateindices.c.gcov'

Lines executed:100.00% of 24
'/usr/bin/gcov' '/home/michael/github/data.table/src/openmp-utils.gcno' '-p'
'-o' '/home/michael/github/data.table/src'

File 'openmp-utils.c'
Lines executed:89.01% of 91
Creating 'openmp-utils.c.gcov'

Lines executed:89.01% of 91
'/usr/bin/gcov' '/home/michael/github/data.table/src/programming.gcno' '-p'
'-o' '/home/michael/github/data.table/src'

File 'programming.c'
Lines executed:100.00% of 24
Creating 'programming.c.gcov'

Lines executed:100.00% of 24
'/usr/bin/gcov' '/home/michael/github/data.table/src/quickselect.gcno' '-p'
'-o' '/home/michael/github/data.table/src'

File 'quickselect.c'
Lines executed:100.00% of 9
Creating 'quickselect.c.gcov'

Lines executed:100.00% of 9
'/usr/bin/gcov' '/home/michael/github/data.table/src/rbindlist.gcno' '-p'
'-o' '/home/michael/github/data.table/src'

File 'rbindlist.c'
Lines executed:95.91% of 391
Creating 'rbindlist.c.gcov'

Lines executed:95.91% of 391
'/usr/bin/gcov' '/home/michael/github/data.table/src/reorder.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'reorder.c'
Lines executed:98.63% of 73
Creating 'reorder.c.gcov'

Lines executed:98.63% of 73
'/usr/bin/gcov' '/home/michael/github/data.table/src/shift.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'shift.c'
Lines executed:98.55% of 138
Creating 'shift.c.gcov'

Lines executed:98.55% of 138
'/usr/bin/gcov' '/home/michael/github/data.table/src/snprintf.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'snprintf.c'
Lines executed:88.51% of 148
Creating 'snprintf.c.gcov'

Lines executed:88.51% of 148
'/usr/bin/gcov' '/home/michael/github/data.table/src/subset.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'subset.c'
Lines executed:95.98% of 224
Creating 'subset.c.gcov'

Lines executed:95.98% of 224
'/usr/bin/gcov' '/home/michael/github/data.table/src/transpose.gcno' '-p'
'-o' '/home/michael/github/data.table/src'

File 'transpose.c'
Lines executed:100.00% of 84
Creating 'transpose.c.gcov'

Lines executed:100.00% of 84
'/usr/bin/gcov' '/home/michael/github/data.table/src/types.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'types.c'
Lines executed:97.96% of 49
Creating 'types.c.gcov'

Lines executed:97.96% of 49
'/usr/bin/gcov' '/home/michael/github/data.table/src/uniqlist.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'uniqlist.c'
Lines executed:95.87% of 242
Creating 'uniqlist.c.gcov'

Lines executed:95.87% of 242
'/usr/bin/gcov' '/home/michael/github/data.table/src/utils.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'utils.c'
Lines executed:95.57% of 271
Creating 'utils.c.gcov'

Lines executed:95.57% of 271
'/usr/bin/gcov' '/home/michael/github/data.table/src/vecseq.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'vecseq.c'
Lines executed:100.00% of 25
Creating 'vecseq.c.gcov'

Lines executed:100.00% of 25
'/usr/bin/gcov' '/home/michael/github/data.table/src/wrappers.gcno' '-p' '-o'
'/home/michael/github/data.table/src'

File 'wrappers.c'
Lines executed:100.00% of 64
Creating 'wrappers.c.gcov'

Lines executed:100.00% of 64

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