$ git clone -n https://src.fedoraproject.org/rpms/R-brio.git /var/lib/mock/f45-build-5993-345/root/chroot_tmpdir/scmroot/R-brio
Cloning into '/var/lib/mock/f45-build-5993-345/root/chroot_tmpdir/scmroot/R-brio'...
$ git fetch origin 0bac2e3697c30a02a834de79d9bb39dcaaff7a1a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-brio
 * [new ref]         0bac2e3697c30a02a834de79d9bb39dcaaff7a1a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 0bac2e3 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild