Pull request limits for CPython repo

We’ve set a limit for the maximum number of PRs you can open at python/cpython to 3, including drafts. This does not affect members of the core or triage teams. If you have more than 3 PRs already open, they stay open, but you won’t be able to open another before dropping below the limit. We have done this following several recent incidents of bulk PR creation in a short amount of time, and we’re struggling to handle them. For example: Today: 21 CPython PRs opened in a single two-hou...