$ git clone -n https://src.fedoraproject.org/rpms/R-rjson.git /var/lib/mock/f40-build-789211-135680/root/chroot_tmpdir/scmroot/R-rjson
Cloning into '/var/lib/mock/f40-build-789211-135680/root/chroot_tmpdir/scmroot/R-rjson'...
$ git fetch origin 0af744be11d4f51de65af7d8fd2c3d73cfa592a4:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-rjson
 * [new ref]         0af744be11d4f51de65af7d8fd2c3d73cfa592a4 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 0af744b Rebuilt for https://fedoraproject.org/wiki/Fedora_40_Mass_Rebuild