REGR: NumPy func warning when dropping nuisance in agg, apply, transform
- [x] closes #50538 (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.
- [x] Added an entry in the latest `doc/source/whatsnew/vX.X.X.rst` file if fixing a bug or adding a new feature.

@jorisvandenbossche @jbrockmendel @mroeschke for any thoughts/feedback In case we keep the current behaviour (no special handling of `numeric_only`, just passing through), then this is at least a clear improvement in the warning messages! @jorisvandenbossche - I think trying to change the pass through behavior is too tricky for a patch (this is targeted to go straight into 1.5.3). I do plan to work on it for future versions (e.g. #50624). If you want this to not close #50538, I can remove it from the OP here, but I do think this is the safest route for 1.5.3. @mroeschke - friendly ping. Thanks @rhshadrach 