$ git clone -n https://src.fedoraproject.org/rpms/postgis.git /var/lib/mock/f39-build-2036183-47992/root/chroot_tmpdir/scmroot/postgis
Cloning into '/var/lib/mock/f39-build-2036183-47992/root/chroot_tmpdir/scmroot/postgis'...
$ git fetch origin 6ebe48e61500e054c70a637a594c4de4e131fe95:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/postgis
 * [new ref]         6ebe48e61500e054c70a637a594c4de4e131fe95 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 6ebe48e Update to 3.3.4