$ git clone -n https://src.fedoraproject.org/rpms/spew.git /var/lib/mock/f38-build-side-42-init-devel-1381992-30706/root/chroot_tmpdir/scmroot/spew
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-1381992-30706/root/chroot_tmpdir/scmroot/spew'...
$ git fetch origin b9d4a1c182a29a3a51dfc139eb9cce755e36b21a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/spew
 * [new ref]         b9d4a1c182a29a3a51dfc139eb9cce755e36b21a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b9d4a1c Rebuilt for https://fedoraproject.org/wiki/Fedora_38_Mass_Rebuild