DOC: fix DataFrame.quantile docstring and doctests

[Moisan]

• closes DOC: Fix the docstring of quantile in pandas/core/frame.py #22898
• tests added / passed
• passes git diff upstream/master -u -- "*.py" | flake8 --diff

Based on #22459. Fix the docstring for DataFrame.quantile. I also updated ci/code_checks.sh.

[pep8speaks]

Hello @Moisan! Thanks for submitting the PR.

• There are no PEP8 issues in the file pandas/core/frame.py !

[Moisan]

Crap forgot to double check the open pull requests before working on this. Closing in favor of #22906.

[codecov]

Codecov Report

Merging #23936 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master   #23936   +/-   ##
=======================================
  Coverage    92.2%    92.2%           
=======================================
  Files         162      162           
  Lines       51700    51700           
=======================================
  Hits        47669    47669           
  Misses       4031     4031

Flag	Coverage Δ
#multiple	90.6% <ø> (ø)	⬆️
#single	43.02% <ø> (ø)	⬆️

Impacted Files	Coverage Δ
pandas/core/frame.py	96.91% <ø> (ø)	⬆️

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[datapythonista]

@Moisan, #22906 is stale. Reopening this. If you don't mind taking a look at the discussions there, and finish the changes here, that would be great.

[datapythonista]

lgtm, thanks @Moisan

the CI is currently broken, you'll have to merge maste when #24160 is fixed, so we can see everything is green.

[datapythonista]

@Moisan can you merge master and push again. CI is fixed now.

[jreback]

thanks @Moisan