Fix a crash in the unsupported-membership-test checker when assigning
multiple constants to class attributes including __iter__ via unpacking.

Closes #6366

Asterisks are no longer required in Sphinx and Google style parameter documentation
for missing-param-doc and are parsed correctly.

Closes #5815
Closes #5406

Fixed a false positive for unused-variable when a builtin specified in
--additional-builtins is given a type annotation.

Closes #6388

Fixed an AstroidError in 2.13.0 raised by the duplicate-code checker with
ignore-imports or ignore-signatures enabled.

Closes #6301