Why:

Closes #4327

The Filtering email notifications section of the Configuring notifications documentation lists the ways in which GitHub includes notification metadata in notification emails. Part of that metadata is the Cc field which includes a reason why the user is receiving the email.

Currently, email notifications about completed action runs are sent with ci_activity@noreply.github.com in the Cc field. This is not documented here, so I believe it should be added.

What's being changed:

I've added the following element to the Cc row in the table:

• ci_activity: An action run that you initiated finished.

I'm not completely sure about the wording here. I chose not to use the GitHub Actions product name because this is referring to an instance of a GitHub Actions "thing". I also wasn't sure if "action run" is necessary or simply "action" is sufficient. I'll differ to you for the specific terminology that should be used (e.g. workflow, action, ci run, etc.)

Also, as noted in #4327, I don't know if the wording should be modified to not be exclusive to GitHub Actions CI. If non-GHA CI would also trigger these notifications, it may make more sense to use generic wording such as:

• ci_activity: A CI run that you initiated finished.

Check off the following:

• I have reviewed my changes in staging. (look for the deploy-to-heroku link in your pull request, then click View deployment)
• For content changes, I have reviewed the localization checklist
• For content changes, I have reviewed the Content style guide for GitHub Docs.