$ git clone -n https://src.fedoraproject.org/rpms/R-highlight.git /var/lib/mock/f45-build-6164-346/root/chroot_tmpdir/scmroot/R-highlight
Cloning into '/var/lib/mock/f45-build-6164-346/root/chroot_tmpdir/scmroot/R-highlight'...
$ git fetch origin 49e1a24f276f549697f190b82513f0c6ff5c908a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-highlight
 * [new ref]         49e1a24f276f549697f190b82513f0c6ff5c908a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 49e1a24 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild