$ git clone -n https://src.fedoraproject.org/rpms/glib2.git /var/lib/mock/f41-build-824531-154174/root/chroot_tmpdir/scmroot/glib2
Cloning into '/var/lib/mock/f41-build-824531-154174/root/chroot_tmpdir/scmroot/glib2'...
$ git fetch origin 9a5b9c27124679f83e7e1d394d6eeba0c8fef0a3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/glib2
 * [new ref]         9a5b9c27124679f83e7e1d394d6eeba0c8fef0a3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9a5b9c2 Update to 2.81.0