FAPI TEST: rework test certifcate creation #516

Job	Run time
test-coverage	5m 18s
scanbuild	6m 22s
coverity-test	0s
build-test (ubuntu-18.04, gcc)	3m 11s
test-fuzz	2m 35s
build-test (ubuntu-18.04, clang)	3m 10s
test-mbedtls (ubuntu-20.04)	2m 49s
build-test (ubuntu-20.04, gcc)	3m 9s
test-no-crypto-build	1m 32s
test-mbedtls (ubuntu-22.04-mbedtls-3.1)	2m 51s
build-test (ubuntu-20.04, clang)	3m 12s
test-tcti-config	14m 4s
build-test (fedora-32, gcc)	3m 11s
build-test (fedora-32, clang)	3m 11s
build-test (opensuse-leap, gcc)	3m 11s
build-test (opensuse-leap, clang)	3m 12s
build-test (ubuntu-22.04, gcc)	2m 56s
build-test (ubuntu-22.04, clang)	2m 52s
build-test (alpine-3.15, gcc)	3m 12s
build-test (alpine-3.15, clang)	3m 16s
	1h 13m 14s

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