DEPR: special-cased downcasting in DataFrame.where GH#44597
- [x] closes #44597
- [x] tests added / passed
- [x] Ensure all linting tests pass, see [here](https://pandas.pydata.org/pandas-docs/dev/development/contributing_codebase.html#pre-commit) for how to run them
- [x] whatsnew entry

hmm lots of failures hmm timeouts.... > hmm timeouts....

the last one was ArrayManager, now looks like its complaining 'zstandard' isnt installed. > > hmm timeouts....
> 
> the last one was ArrayManager, now looks like its complaining 'zstandard' isnt installed.

yeah this is a problem on master rn