[3.11] gh-105834: Backport new tests for `typing.Protocol` (#105835) by AlexWaygood · Pull Request #105860 · python/cpython
(cherry-picked from commit 70c075c)
This actually backports some adjacent tests as well, which currently exist on main and 3.12 but not on 3.11. These tests weren't part of #105835, but (1) the tests all pass on 3.11; (2) more test coverage never hurts; and (3) backporting these tests will reduce the risk of merge conflicts when backporting test-only PRs in the future.