Don't use Cython resolver for resolving references to __init__.py (PY-13554, PY-14102)

Normal resolvers should do their job with __init__.py. Using the Cython
resolver instead resulted in bypassing class type to instance type
casting for docstring type references to classses in nested packages.
Merge branch 'python-fixes'
unused declaration: add refs on functional interface from functional expressions (IDEA-132138)
style