$ git clone -n https://src.fedoraproject.org/rpms/rfcdiff.git /var/lib/mock/f39-build-1456834-32939/root/chroot_tmpdir/scmroot/rfcdiff
Cloning into '/var/lib/mock/f39-build-1456834-32939/root/chroot_tmpdir/scmroot/rfcdiff'...
$ git fetch origin 72f998eeaf3ff246cb7ad6d43e0311a749693b37:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rfcdiff
 * [new ref]         72f998eeaf3ff246cb7ad6d43e0311a749693b37 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 72f998e Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild