code: @Override
    public RecordStreamWithMetadata<DO, SO> processStream(RecordStreamWithMetadata<DI, SI> inputStream,
        WorkUnitState workUnitState) throws SchemaConversionException {
      return this.embeddedConverter.processStream(inputStream, workUnitState);
    }
docs: This workarounds the issue that {@link Converter#processStream(RecordStreamWithMetadata, WorkUnitState)} will invoke
  {@link org.apache.gobblin.converter.AsyncConverter1to1#convertRecord(Object, Object, WorkUnitState)} directly, which is an unsupported method.