fix: Fix join literal behavior

[ritchie46]

Rewrite IR so that literals get expanded.

closes #20061
closes #9603

[codecov]

Codecov Report

Attention: Patch coverage is 99.20635% with 1 line in your changes missing coverage. Please review.

Project coverage is 78.99%. Comparing base (0a7814b) to head (128fc63).
Report is 4 commits behind head on main.

Files with missing lines	Patch %	Lines
crates/polars-plan/src/plans/conversion/join.rs	99.09%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #20477      +/-   ##
==========================================
+ Coverage   78.98%   78.99%   +0.01%     
==========================================
  Files        1563     1563              
  Lines      220570   220650      +80     
  Branches     2490     2492       +2     
==========================================
+ Hits       174218   174307      +89     
+ Misses      45779    45770       -9     
  Partials      573      573              

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[mcrumiller]

Based on the PR title, does this also close #9603?

[ritchie46]

Based on the PR title, does this also close #9603?

Yes!