$ git clone -n https://src.fedoraproject.org/rpms/trellis.git /var/lib/mock/f40-build-1824149-24918/root/chroot_tmpdir/scmroot/trellis
Cloning into '/var/lib/mock/f40-build-1824149-24918/root/chroot_tmpdir/scmroot/trellis'...
$ git fetch origin b0ed6f279605104526d01adc3b12f695e7cc67e6:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/trellis
 * [new ref]         b0ed6f279605104526d01adc3b12f695e7cc67e6 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b0ed6f2 update to new snapshot