DEPR: Enforce deprecation of Categorical.min/max(numeric_only)
- [x] Added an entry in the latest `doc/source/whatsnew/vX.X.X.rst` file if fixing a bug or adding a new feature.

Added in https://github.com/pandas-dev/pandas/pull/27929

needs whatsnew, otherwise lgtm thx @mroeschke (Please update the deprecations issue)