$ git clone -n https://src.fedoraproject.org/rpms/R-RcppDate.git /var/lib/mock/f45-build-5900-345/root/chroot_tmpdir/scmroot/R-RcppDate
Cloning into '/var/lib/mock/f45-build-5900-345/root/chroot_tmpdir/scmroot/R-RcppDate'...
$ git fetch origin 390a563e8960069cc3de2be2d6ff5c928ef5a841:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-RcppDate
 * [new ref]         390a563e8960069cc3de2be2d6ff5c928ef5a841 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 390a563 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild