TYP: Add typing.overload signatures to DataFrame/Series.interpolate
This adds overloads so that a type checker can determine whether interpolate returns DataFrame/Series or None based on the value of the inplace argument.

This is more of the same thing that was done in [this pull](https://github.com/pandas-dev/pandas/pull/54281).
pre-commit.ci autofix Thank you @caneff! 

Pyright/mypy pass, CI failures seem unrelated.