Update pyright CI test to use the latest version of pyright (1.1.118). Enable all but one of pyright's strictest checks. Add a "# type: ignore" to `__new__` method in `weakref.KeyRef` because it uses a non-standard name for the `cls` parameter, which is flagged as an error by pyright.
Co-authored-by: Eric Traut <erictr@microsoft.com>