DOC: Fixing even more warnings (not many left)
- [X] xref #24173
- [ ] tests added / passed
- [ ] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [ ] whatsnew entry

Let's wait for the logs, tested locally only part of them, but this should fix most of the remaining warnings.

CC: @jorisvandenbossche 