[lldb][docs] Filter out 'thisown' attribute and inheritance boilerplate
This patch implements a filter that post-processes some of the generated RST sources
of the Python API docs. I mainly want to avoid two things:
- Filter out all the inheritance boilerplate that just keeps mentioning for
every class that it inherits from the builtin 'object'. There is no inheritance
in the SB API.
- More importantly, removes the SWIG generated thisown attribute from the
public documentation. I don't think we want users to mess with that attribute
and this is probably causing more confusion than it would help anyone. It also
makes the documentation for some smaller classes more verbose than necessary.
This patch just uses the sphinx event for reading source and removes the parts
that we don't want in documentation.
Reviewed By: JDevlieghere
Differential Revision: https://reviews.llvm.org/D94967