GitLab is used only for code review, issue tracking and project management. Canonical locations for source code are still https://gitweb.torproject.org/ https://git.torproject.org/ and git-rw.torproject.org.
At the bottom of e.g. https://gitweb.torproject.org/exonerator.git/ it sends us to http://dccbbv6cooddgcrq.onion/exonerator.git.
(If there is a gitweb or git-admin repo in gitlab, please send this ticket there. :)