REF: remove Block.putmask fallback to where
- [ ] closes #xxxx
- [ ] tests added / passed
- [ ] 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
- [ ] whatsnew entry

Works locally, curious to see how it fares on other builds.
looks fine here, ok? > looks fine here, ok?

yah, should be good to go inching closer to de-duplicating Block methods.