BUG: Correct numeric_only default for resample var and std
- [x] closes #46560 (Replace xxxx with the Github issue number)
- [x] [Tests added and passed](https://pandas.pydata.org/pandas-docs/dev/development/contributing_codebase.html#writing-tests) if fixing a bug or adding a new feature
- [x] All [code checks passed](https://pandas.pydata.org/pandas-docs/dev/development/contributing_codebase.html#pre-commit).
- [x] Added [type annotations](https://pandas.pydata.org/pandas-docs/dev/development/contributing_codebase.html#type-hints) to new arguments/methods/functions.
- [ ] Added an entry in the latest `doc/source/whatsnew/vX.X.X.rst` file if fixing a bug or adding a new feature.

No whatsnew since this was introduced in 1.5.0. The test would have caught it but it was explicitly passing `numeric_only=lib.no_default` instead of just not passing any arg.

As far as I know, this was the last task for #46560.
Awesome work @rhshadrach! This was a herculean effort 🎉  Thanks for all the reviews @mroeschke!