Fixed writing required list to parquet

[jorgecarleitao]

It unfortunately slipped through the tests :(

Closes #967 - thanks @mpetri for the report!

[codecov]

Codecov Report

Merging #968 (3b641b1) into main (9ecb8ef) will increase coverage by 0.02%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #968      +/-   ##
==========================================
+ Coverage   71.44%   71.47%   +0.02%     
==========================================
  Files         355      355              
  Lines       19572    19580       +8     
==========================================
+ Hits        13984    13994      +10     
+ Misses       5588     5586       -2     

Impacted Files	Coverage Δ
src/io/parquet/write/levels.rs	97.05% <100.00%> (+2.37%)	⬆️

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