$ git clone -n https://src.fedoraproject.org/rpms/R-rsvg.git /var/lib/mock/f45-build-6375-348/root/chroot_tmpdir/scmroot/R-rsvg
Cloning into '/var/lib/mock/f45-build-6375-348/root/chroot_tmpdir/scmroot/R-rsvg'...
$ git fetch origin b33b19340258060290edf66feff4fdb76e397b0d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-rsvg
 * [new ref]         b33b19340258060290edf66feff4fdb76e397b0d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b33b193 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild