$ git clone -n https://src.fedoraproject.org/rpms/compsize.git /var/lib/mock/f45-build-4866-334/root/chroot_tmpdir/scmroot/compsize
Cloning into '/var/lib/mock/f45-build-4866-334/root/chroot_tmpdir/scmroot/compsize'...
$ git fetch origin 51cab42191b33fa7a5efe5a804a1bbf554db2074:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/compsize
 * [new ref]         51cab42191b33fa7a5efe5a804a1bbf554db2074 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 51cab42 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild