Consider allowing renovate to auto-merge PRs without approval

If renovate is the only user on a PR and all tests succeed, we can probably automatically squash & merge that PR. This would need to go alongside appropriate renovate configuration, but a configuration that automatically merges only patch updates would probably be sufficient.

Start by locating the repository's Renovate configuration and CI merge rules. Check how to limit automatic merges to Renovate-only PRs, successful tests, and patch updates, then verify that the resulting configuration safely squash-merges matching PRs without approval.

Written by the indexing model from the issue text.