@Override
      public void close() throws IOException {
        iterator.close();
      }
This class is a temporary implementation, as readData and readDeleteData need to read the delete
file twice. Later on, it will be changed to read the delete file only once. Can read both
Mixed-hive and Mixed-iceberg format.
amoro-format-mixed/amoro-mixed-hive/src/main/java/org/apache/amoro/hive/optimizing/MixedHiveOptimizingDataReader.java