public static ConfigNodeDescriptor getInstance() {
    return ConfigNodeDescriptorHolder.INSTANCE;
  }
Check if the current ConfigNode is SeedConfigNode.

<p>Notice: Only invoke this interface when first startup.

@return True if the seed_config_node points to itself
iotdb-core/confignode/src/main/java/org/apache/iotdb/confignode/conf/ConfigNodeDescriptor.java