The ZUULCONF repository was pointing to the Github URL https://github.com/wikimedia/integration-zuul-config.git
I changed it to point to the Gerrit URL: https://gerrit.wikimedia.org/r/integration/zuul-config but Fabricator refuses to change the remote URL.
Working copy OK: /fab/git/ZUULCONF
Error updating working copy: Working copy at "/fab/git/ZUULCONF/" has a mismatched origin URI: "https://github.com/wikimedia/integration-zuul-config.git". The expected origin URI is "https://gerrit.wikimedia.org/r/integration/zuul-config". Fix your configuration, or set the remote URI correctly. To avoid breaking anything, Phabricator will not automatically fix this.
It is probably a good thing, but I have no idea how one can fix it.
Assigning to Quim for triaiging, since we might want to have this reported back to Upstream.