Fix typos, use logging.warning

[kinow]

Hi,

Two commits here, but happy to squash if necessary. Found a typo in the docs for new contributors (double "like" in https://pydata-sphinx-theme.readthedocs.io/en/stable/contribute/manual.html).

So I ran the PyCharm linter, and added the other typos found in code comments.

The other commit is for logging.warn, which was deprecated in 3.3 and is to be removed some day 👍

Thanks!
-Bruno

[12rambau]

Thanks for taking the time for a PR! nothing to add from my side

[choldgraf]

many thanks for all of these improvements :-) LGTM