How can I link tests to bug reports?

I'm trying to run WordPress automated tests as described in this article. Predictably, I've been getting a lot of skipped tests marked S, because, according to the article, "this usually means that the test is linked to a bug report, and that bug report remains unfixed." I'd like to link tests to bug reports, too, but I'm having difficulty finding information about how to do that. How can I link a test to a bug report? Can I do that with GitHub issues, too?