fix: Fix incorrect filter after right-join on LazyFrame

[nameexhaustion]

Fixes #19772

[codecov]

Codecov Report

Attention: Patch coverage is 88.88889% with 1 line in your changes missing coverage. Please review.

Project coverage is 79.55%. Comparing base (420c0d9) to head (a1a06c6).
Report is 4 commits behind head on main.

Files with missing lines	Patch %	Lines
...lan/src/plans/optimizer/predicate_pushdown/join.rs	88.88%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #19775   +/-   ##
=======================================
  Coverage   79.55%   79.55%           
=======================================
  Files        1544     1544           
  Lines      213240   213243    +3     
  Branches     2441     2441           
=======================================
+ Hits       169645   169648    +3     
  Misses      43046    43046           
  Partials      549      549           

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[nameexhaustion]

I think we forgot to update this function when we added Right join, and it silently passed because of the _ => catch-all

[ritchie46]

Don't silently catch all. :|