$ git clone -n https://src.fedoraproject.org/rpms/gnome-shell.git /var/lib/mock/f41-build-1291165-23357/root/chroot_tmpdir/scmroot/gnome-shell
Cloning into '/var/lib/mock/f41-build-1291165-23357/root/chroot_tmpdir/scmroot/gnome-shell'...
$ git fetch origin c3c6dfa9cc6360770bde6e30b9d57650ebc5ccda:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gnome-shell
 * [new ref]         c3c6dfa9cc6360770bde6e30b9d57650ebc5ccda -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c3c6dfa Update to 47.alpha