$ git clone -n https://src.fedoraproject.org/rpms/varnish.git /var/lib/mock/f40-build-2206605-52059/root/chroot_tmpdir/scmroot/varnish
Cloning into '/var/lib/mock/f40-build-2206605-52059/root/chroot_tmpdir/scmroot/varnish'...
$ git fetch origin 448cc6b4c0ab994d358d94268d4ae1178b054a5c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/varnish
 * [new ref]         448cc6b4c0ab994d358d94268d4ae1178b054a5c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 448cc6b Upload varnish-7.4.2.tgz