fix: Do not check dtypes of non-projected columns for parquet

[nameexhaustion]

Fixes #19249

[codecov]

Codecov Report

Attention: Patch coverage is 76.92308% with 3 lines in your changes missing coverage. Please review.

Project coverage is 80.03%. Comparing base (9376ce3) to head (e3820bb).
Report is 4 commits behind head on main.

Files with missing lines	Patch %	Lines
crates/polars-io/src/parquet/read/reader.rs	83.33%	2 Missing ⚠️
...-stream/src/nodes/parquet_source/metadata_fetch.rs	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #19254      +/-   ##
==========================================
+ Coverage   80.00%   80.03%   +0.02%     
==========================================
  Files        1527     1528       +1     
  Lines      209211   209572     +361     
  Branches     2415     2415              
==========================================
+ Hits       167377   167725     +348     
- Misses      41286    41299      +13     
  Partials      548      548              

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