$ git clone -n https://src.fedoraproject.org/rpms/gap-pkg-images.git /var/lib/mock/f40-build-2664386-67052/root/chroot_tmpdir/scmroot/gap-pkg-images
Cloning into '/var/lib/mock/f40-build-2664386-67052/root/chroot_tmpdir/scmroot/gap-pkg-images'...
$ git fetch origin 385fc8c6298ffff960733c56fdb93089732bd923:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gap-pkg-images
 * [new ref]         385fc8c6298ffff960733c56fdb93089732bd923 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 385fc8c Version 1.3.2