@Override
    public void close() throws IOException {
      io.doAs(
          () -> {
            iterator.close();
            return null;
          });
    }
Iterator for reading data in a Merge on Read (MOR) way. This iterator handles reading data from
an Amoro mix-format table while keeping track of file and record offsets for efficient data
retrieval.
amoro-format-mixed/amoro-mixed-flink/amoro-mixed-flink-common/src/main/java/org/apache/amoro/flink/read/source/MergeOnReadDataIterator.java