$ git clone -n https://src.fedoraproject.org/rpms/rear.git /var/lib/mock/f38-build-side-42-init-devel-1068297-29783/root/chroot_tmpdir/scmroot/rear
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-1068297-29783/root/chroot_tmpdir/scmroot/rear'...
$ git fetch origin 5acc2d3b71d9c91bab94c5008bce4511077d458f:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rear
 * [new ref]         5acc2d3b71d9c91bab94c5008bce4511077d458f -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5acc2d3 Rebuilt for https://fedoraproject.org/wiki/Fedora_38_Mass_Rebuild