docs: public ClusterInfo getClusterInfoOrNull() {
          String clusterName = getProperty(InternalConfigurationOptions.INTERNAL_ES_CLUSTER_NAME);
          if (clusterName == null) {
              return null;
          }
          String clusterUUID = getProperty(InternalConfigurationOptions.INTERNAL_ES_CLUSTER_UUID);
          EsMajorVersion version = getInternalVersionOrThrow();
          return new ClusterInfo(new ClusterName(clusterName, clusterUUID), version);
      }