$ git clone -n https://src.fedoraproject.org/rpms/spectacle.git /var/lib/mock/f42-build-881302-183509/root/chroot_tmpdir/scmroot/spectacle
Cloning into '/var/lib/mock/f42-build-881302-183509/root/chroot_tmpdir/scmroot/spectacle'...
$ git fetch origin 04403f6787d90d626859b34509ebbec37d76a80c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/spectacle
 * [new ref]         04403f6787d90d626859b34509ebbec37d76a80c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 04403f6 6.3.2