whitelist->allowlist in tox.ini

[damccorm]

Tox has changed this name - https://tox.wiki/en/latest/config.html#allowlist_externals

This has been supported since 3.18.0 - https://tox.wiki/en/3.18.1/changelog.html#v3-18-0-2020-07-23 and is now fully removed in tox >=4. Without this change, some tooling doesn't work on the newest tox

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[damccorm]

Run PythonDocs PreCommit

[codecov]

Codecov Report

Merging #25647 (ccdd32c) into master (fabd1f6) will increase coverage by 0.02%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master   #25647      +/-   ##
==========================================
+ Coverage   72.79%   72.82%   +0.02%     
==========================================
  Files         775      775              
  Lines      102863   102928      +65     
==========================================
+ Hits        74877    74953      +76     
+ Misses      26532    26522      -10     
+ Partials     1454     1453       -1     

Flag	Coverage Δ
python	81.95% <ø> (+0.02%)	⬆️

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

Impacted Files	Coverage Δ
sdks/python/apache_beam/io/textio.py	94.59% <0.00%> (-2.47%)	⬇️
sdks/python/apache_beam/utils/interactive_utils.py	95.12% <0.00%> (-2.44%)	⬇️
sdks/python/apache_beam/io/fileio.py	96.12% <0.00%> (+0.04%)	⬆️
...python/apache_beam/runners/worker/worker_status.py	75.33% <0.00%> (+0.66%)	⬆️
sdks/python/apache_beam/io/localfilesystem.py	91.72% <0.00%> (+0.75%)	⬆️
...o/pkg/beam/runners/prism/internal/worker/worker.go	64.59% <0.00%> (+1.94%)	⬆️
sdks/python/apache_beam/dataframe/io.py	92.55% <0.00%> (+3.48%)	⬆️

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[github-actions]

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