Enhance protocol matching support to take into consideration final attributes

[erictraut]

Currently, pyright doesn't take into consideration a class or instance variable that is annotated as Final within a Protocol class. Nor does it take into account a final=True dataclass protocol.

See: python/mypy#10850

[erictraut]

This will be addressed in the next release.

[erictraut]

This is now addressed in pyright 1.1.159, which I just published. It will also be included in the next release of pylance.