refactor: Remove Growable in favor of ArrayBuilder

[orlp]

This replaces the last usage of the Growable (in the filter and if-then-else for nested types), allowing us to remove it.

[codecov]

Codecov Report

Attention: Patch coverage is 79.08497% with 32 lines in your changes missing coverage. Please review.

Project coverage is 79.84%. Comparing base (823bfc9) to head (398e25a).
Report is 3 commits behind head on main.

Files with missing lines	Patch %	Lines
crates/polars-arrow/src/array/builder.rs	34.37%	21 Missing ⚠️
crates/polars-arrow/src/array/null.rs	21.42%	11 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #21500      +/-   ##
==========================================
+ Coverage   79.73%   79.84%   +0.11%     
==========================================
  Files        1605     1592      -13     
  Lines      230053   229179     -874     
  Branches     2623     2623              
==========================================
- Hits       183424   182987     -437     
+ Misses      46024    45587     -437     
  Partials      605      605              

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