Get notified when a GitHub action completes

Often I’m waiting to merge a PR until all of its checks have passed. While I do my best to keep checks as fast as possible they still take long enough that I’m not going to wait for them to finish. I start something new while I wait. Frequently I then forget to merge the PR because I’m completely caught up in the next thing. This is even worse for PRs where I’m testing changes to the GitHub…