$ git clone -n https://src.fedoraproject.org/rpms/mozilla-ublock-origin.git /var/lib/mock/f41-build-1022484-18078/root/chroot_tmpdir/scmroot/mozilla-ublock-origin
Cloning into '/var/lib/mock/f41-build-1022484-18078/root/chroot_tmpdir/scmroot/mozilla-ublock-origin'...
$ git fetch origin ba671ffda2c7084a95d36e28579d958c0dff7a3c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/mozilla-ublock-origin
 * [new ref]         ba671ffda2c7084a95d36e28579d958c0dff7a3c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ba671ff +- update Firefox app ID reference (#2279889)