fix: Py-polars compilation with no features

[coastalwhite]

This fixes the compilation of py-polars with no features.

And should address the compilation failure in #18117.

[codecov]

Codecov Report

Attention: Patch coverage is 18.18182% with 18 lines in your changes missing coverage. Please review.

Project coverage is 80.33%. Comparing base (bc65bd0) to head (5138fb2).

Files	Patch %	Lines
py-polars/src/lazyframe/visitor/expr_nodes.rs	0.00%	18 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #18129      +/-   ##
==========================================
- Coverage   80.35%   80.33%   -0.02%     
==========================================
  Files        1496     1496              
  Lines      197685   197689       +4     
  Branches     2821     2821              
==========================================
- Hits       158845   158809      -36     
- Misses      38319    38359      +40     
  Partials      521      521              

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