public List<String> getDatabaseNames(final Boolean isTableModel) {
    return clusterSchemaInfo.getDatabaseNames(isTableModel).stream()
        .filter(this::isDatabaseExist)
        .collect(Collectors.toList());
  }
Only leader use this interface. Get all the databases' names under the specific model. For some
common services on configNode, the input shall be {@code null} to extract the databases from
both models.

@param isTableModel {@link Boolean#TRUE} is only extract table model database, {@link
    Boolean#FALSE} is only extract tree model database, {@code null} is extract both.
@return List{@literal <}DatabaseName{@literal >}, all Databases' name
iotdb-core/confignode/src/main/java/org/apache/iotdb/confignode/manager/schema/ClusterSchemaManager.java