Use built-in csv and json readers.

[robertwb]

No need for these extra wrappers now.

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[robertwb]

R: @damondouglas

[github-actions]

Stopping reviewer notifications for this pull request: review requested by someone other than the bot, ceding control

[codecov]

Codecov Report

Merging #25916 (c637363) into master (fcf51fb) will increase coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master   #25916      +/-   ##
==========================================
+ Coverage   71.40%   71.42%   +0.01%     
==========================================
  Files         778      778              
  Lines      102430   102452      +22     
==========================================
+ Hits        73144    73175      +31     
+ Misses      27830    27821       -9     
  Partials     1456     1456              

Flag	Coverage Δ
python	79.97% <ø> (+0.01%)	⬆️

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Impacted Files	Coverage Δ
sdks/python/apache_beam/yaml/yaml_provider.py	62.79% <ø> (-0.68%)	⬇️

... and 11 files with indirect coverage changes

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[robertwb]

apache_beam.io.gcp.bigquery_test.PipelineBasedStreamingInsertTest.test_batch_size_with_auto_sharding_0 looks irrelevant.

[damondouglas]

@robertwb LGTM I'm assuming the failing checks have nothing to do with this code.

[robertwb]

Run Python PreCommit

[robertwb]

Turns out the errors are related--windows uses backslashes for paths which are interpreted as escapes in the yaml. Blech. Pushed a fix.