GitLab repository accounts now have a special widget to allow the use to

choose between gitlab.com-hosted and self-hosted GitLab instances. In

addition, the field is now validated to ensure that it has a valid URL

scheme. Previously if the scheme was omitted a repository not found

error would occur, even for otherwise valid URLs (e.g., gitlab.com vs

https://gitlab.com).

Added a gitlab.com repository: it worked as expected.
Added a repository with an invalid URL: the new error message was

  provided instead of the old one.