$ git clone -n https://src.fedoraproject.org/rpms/borgmatic.git /var/lib/mock/f39-build-1489664-34501/root/chroot_tmpdir/scmroot/borgmatic
Cloning into '/var/lib/mock/f39-build-1489664-34501/root/chroot_tmpdir/scmroot/borgmatic'...
$ git fetch origin e6d7d53740759df4eaf8c101af92ac8fde14fe7b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/borgmatic
 * [new ref]         e6d7d53740759df4eaf8c101af92ac8fde14fe7b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at e6d7d53 update to 1.8.3