As a user, I would like to remind users to merge their open pull requests

[moberemk]

One issue we have is that stale PRs can linger in the list but there's no direct reminder to the author to merge their open PRs. Ideally there should be a way to encourage that user to actively close their open PRs to prevent them from being forgotten or ignored for long periods of time, and a direct user PM seems like the most effective option for this.