ENH: Add numeric_only to window ops
Part of #46560 

- [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.
- [x] Added an entry in the latest `doc/source/whatsnew/vX.X.X.rst` file if fixing a bug or adding a new feature.

Doh - thanks @mroeschke; test added and implementation fixed for Series case. Awesome thanks @rhshadrach. Was this the final change for https://github.com/pandas-dev/pandas/issues/46560?  @mroeschke - I believe so, but going to be reviewing the API manually to double check things before closing that issue. Will report there and manually close if done.