Feature: Check that CODEOWNERS is up to date

[haydentherapper]

Is your feature request related to a problem? Please describe.
Code owners can be required to approve PRs before merging into a protected branch. Maintainers may rely on code owners to validate the contents of the PRs, so code owners needs to be trusted. Over time, it's easy to continually grow the CODEOWNERS file without keeping it up to date.

Describe the solution you'd like
I propose a scorecard check that the individuals in CODEOWNERS are active contributors. This is especially important for global code owners that can approve code in the entire repository. A threshold may be necessary for handling code owners that only maintain a small subset of files. For example, they may not be an active contributor, but may still be relied on when changes are needed.

I propose that we also check that file paths listed in CODEOWNERS are actually present in the repo. For example, if we delete a directory such as /apps/, then there shouldn't be an owner for this path. If this were not removed and later /apps/ was added back, it may be undesired that the original code owner maintain ownership over that path.

[github-actions]

This issue is stale because it has been open for 60 days with no activity.

[github-actions]

This issue has been marked stale because it has been open for 60 days with no activity.