$ git clone -n https://src.fedoraproject.org/rpms/gravity-beams-and-evaporating-stars.git /var/lib/mock/f39-build-1560104-37331/root/chroot_tmpdir/scmroot/gravity-beams-and-evaporating-stars
Cloning into '/var/lib/mock/f39-build-1560104-37331/root/chroot_tmpdir/scmroot/gravity-beams-and-evaporating-stars'...
$ git fetch origin ef0b85b4d1560e25d29f96de1e16cb7a10f72f5e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gravity-beams-and-evaporating-stars
 * [new ref]         ef0b85b4d1560e25d29f96de1e16cb7a10f72f5e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ef0b85b Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild