public String description() {
    return pkFields.stream()
        .map(PrimaryKeyField::fieldName)
        .collect(Collectors.joining(PRIMARY_KEY_COLUMN_JOIN_DELIMITER));
  }
parse primary key spec from table properties

@param schema - base store table schema
@param keyDescription - key description of {#{@link #description}}
@return primary key spec.
amoro-format-iceberg/src/main/java/org/apache/amoro/table/PrimaryKeySpec.java