[cherry-pick][release-2.38.0][BEAM-14172] Update tox.ini for pydocs (#17176)

[youngoli]

(cherry picked from commit 0c93be1)

Missed this cherry-pick earlier and I need it for RC creation, so I might merge this in before it gets approved and hope for a retroactive approval, just in order to unblock myself. It's a very small change anyway.

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[youngoli]

R: @TheNeuralBit @aaltay

[codecov]

Codecov Report

Merging #17332 (9cc9692) into release-2.38.0 (93ac2a0) will decrease coverage by 0.00%.
The diff coverage is n/a.

@@                Coverage Diff                 @@
##           release-2.38.0   #17332      +/-   ##
==================================================
- Coverage           73.96%   73.96%   -0.01%     
==================================================
  Files                 672      672              
  Lines               88259    88270      +11     
==================================================
+ Hits                65279    65287       +8     
- Misses              21867    21870       +3     
  Partials             1113     1113              

Flag	Coverage Δ
python	83.63% <ø> (-0.01%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...che_beam/runners/interactive/interactive_runner.py	92.85% <0.00%> (-0.72%)	⬇️
...hon/apache_beam/runners/worker/bundle_processor.py	93.26% <0.00%> (-0.25%)	⬇️
.../apache_beam/options/pipeline_options_validator.py	98.90% <0.00%> (+0.03%)	⬆️
...dks/python/apache_beam/options/pipeline_options.py	94.91% <0.00%> (+0.05%)	⬆️

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[youngoli]

Run Python_PVR_Flink PreCommit

[youngoli]

Again, merging this without approval to unblock, will need to get some retroactive approval.

[TheNeuralBit]

LGTM