Cleanup the skipped tests

Cleanup the skipped tests in this list: https://jihulab.com/gitlab-cn/gitlab/-/blob/main-jh/jh/spec/skip_specs/list. For each test in the list, it may need a JH MR (add a test to override the skipped test) or an upstream MR (modify the test to make it compatible between JH and upstream).

In another hand, if we have to skip a test due to an emergency, we'd better not to skip it with a specific line number (e.g. spec/features/users/login_spec.rb:763) since the line number would be invalid if the test was changed in the upstream. So we need to come up with a more robust way to skip tests.