Starting with GitHub Branch Source 2.5.5 (see PR), we now have two ways to set up our remote repo for multibranch projects based on GitHub repositories. This ticket represents the accompanying updates that the acceptance test harness needs in order to make this work.
The new UI offers, and defaults to, the ability to supply a single HTTPS URL, in much the same way you'd copy/paste such a URL into a git clone command. The ATH needs to be modified to accomodate this.
Before the above-mentioned improvement to GitHub Branch Source, users needed to first supply the repository owner. For example, And then, if the repo owner had hundreds or even thousands of repos, it could take a very long time to populate the resulting drop-down menu. My suspicion is that this delay is the reason why the test was set to @Ignore.
It's possible that the ATH will also need to maintain some sort of backward compatibility with the old UI.