CLN: Update docstring decorator from Appender and Substitution to doc #31942
Description
We use to use Appender and Substitution decorators to share docstring cross functions. Now we implemented a new decorator doc for that use case, and it would simplify the reuse of docstrings.
The idea here is to replace Appender and Substitution with doc decorator, and move the shared docstring to a better place if possible.
Example
The original code will be look like this:
@Substitution(**_shared_doc_kwargs)
@Appender(NDFrame.fillna.__doc__)
def fillna(self, value=None, ...) -> Optional["DataFrame"]:
return super().fillna(...)We would like to change it to this:
@doc(NDFrame.fillna, **_shared_doc_kwargs)
def fillna(self, value=None, ...) -> Optional["DataFrame"]:
return super().fillna(...)