[TYPING] Add type overloads for inplace dataframe operations

[tigerhawkvok]

Add type overloads for inplace dataframe operationsctly show a return of None or DataFrame based on flag state.

Additionally adds one small type check function, validate_strict_bool() to wrap validate_bool_kwargs() for inplace, as validate_bool_kwargs() accepts bool or None; but inplace can only be bool.

Aside from that very minor function edit, all other changes are exclusively to type hints.

Simple test case:

from typing import Any, cast
from pyspark.pandas import DataFrame

foo = cast(DataFrame, None).sort_index()
bar = cast(DataFrame, None).sort_index(inplace= True)

bam = bool(cast(Any, None))
baz = cast(DataFrame, None).sort_index(inplace= bam)

Before:

The union is returned regardless of state of inplace

After:

• inplace is implicitly or explicitly True returns a DataFrame
  

• inplace is explicitly False returns None
  

• inplace is ambiguous and either True or False, still returns Union[DataFrame, None]
  
  

[tigerhawkvok]

The lint error for this PR is an open MyPy bug:

python/mypy#11165

[HyukjinKwon]

cc @itholic

[github-actions]

We're closing this PR because it hasn't been updated in a while. This isn't a judgement on the merit of the PR in any way. It's just a way of keeping the PR queue manageable.
If you'd like to revive this PR, please reopen it and ask a committer to remove the Stale tag!