PERF: find_stack_level
- [ ] closes #45099
- [ ] 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

Some low hanging fruit in find_stack_level. 
``pytest pandas/tests/groupby/test_function.py -v -k "test_builtins_apply"`` goes from 35 -> 6 secs for me.
Someone may want to verify. Also IDK how to benchmark this.

@jbrockmendel Would you like to test this locally to verify the perf gains?
> Would you like to test this locally to verify the perf gains?

I'm happy to take your word for it. @mroeschke good here? thanks @lithomas1  wouldn't object to backport ing this @meeseeksdev backport 1.4.x