We have some old contributed code from 2014 that was designed to

validate the bug tracker hosting URL field in the repository form. It

depended heavily on the order in which fields were validated, which is

very fragile, and the way in which it validated the contents made some

assumptions that often do not hold true. It's also just no longer

relevant, as a large part of its purpose was ensuring that a bug tracker

form's validation was respected, and we do that now as of this upcoming

3.0.16 release.
This change removes that layer of validation, simplifying code and

preventing some of the side effects it's triggering in upcoming changes.

Unit tests pass.
Verified this fixed issues with some upcoming changes.