@Override
    protected SnapshotContext prepare(ChangeEventSourceContext changeEventSourceContext)
            throws Exception {
        return new MySqlSnapshotContext();
    }
for chunk that equals to the whole table we do not need to normalize
the snapshot data and the binlog data, just set high watermark to low watermark
@return highWatermark
inlong-sort/sort-flink/sort-flink-v1.13/sort-connectors/mysql-cdc/src/main/java/org/apache/inlong/sort/cdc/mysql/debezium/task/MySqlSnapshotSplitReadTask.java