$ git clone -n https://src.fedoraproject.org/rpms/postgis.git /var/lib/mock/f38-build-side-42-init-devel-1261911-30642/root/chroot_tmpdir/scmroot/postgis
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-1261911-30642/root/chroot_tmpdir/scmroot/postgis'...
$ git fetch origin d8dda98d58a9cec98ea0ca65f98883d421ad2da1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/postgis
 * [new ref]         d8dda98d58a9cec98ea0ca65f98883d421ad2da1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d8dda98 Fix sources