$ git clone -n https://src.fedoraproject.org/rpms/R-Rcpp.git /var/lib/mock/f40-build-789280-135700/root/chroot_tmpdir/scmroot/R-Rcpp
Cloning into '/var/lib/mock/f40-build-789280-135700/root/chroot_tmpdir/scmroot/R-Rcpp'...
$ git fetch origin b51bbcbeb13f642d692d98f3f7e68104628162b3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-Rcpp
 * [new ref]         b51bbcbeb13f642d692d98f3f7e68104628162b3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b51bbcb Rebuilt for https://fedoraproject.org/wiki/Fedora_40_Mass_Rebuild