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.
BridgeDB is written in Python 2.7, which will no longer be maintained past 2020. We should port BridgeDB to Python 3. This may involve quite some work given BridgeDB's large code base and the libraries it depends on.