$ git clone -n https://src.fedoraproject.org/rpms/R-corpus.git /var/lib/mock/f40-build-789318-135723/root/chroot_tmpdir/scmroot/R-corpus
Cloning into '/var/lib/mock/f40-build-789318-135723/root/chroot_tmpdir/scmroot/R-corpus'...
$ git fetch origin c8450b0fc0eb270cbebf885b3803232e8973a536:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-corpus
 * [new ref]         c8450b0fc0eb270cbebf885b3803232e8973a536 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c8450b0 Rebuilt for https://fedoraproject.org/wiki/Fedora_40_Mass_Rebuild