@Override
    public String toString() {
        return MoreObjects.toStringHelper(this)
                          .add("route", route)
                          .add("clusterSnapshot", clusterSnapshot)
                          .toString();
    }
The {@link ClusterSnapshot} that is represented by {@link RouteAction#getCluster()}.
If the {@link RouteAction} does not reference a cluster, the returned value may be {@code null}.
xds/src/main/java/com/linecorp/armeria/xds/RouteEntry.java