@Override
    public void addReader(int subtaskId) {
        // do nothing
    }
Incremental source enumerator that enumerates receive the split request and assign the split to
source readers.
Copy from com.ververica:flink-cdc-base:2.3.0.
inlong-sort/sort-flink/cdc-base/src/main/java/org/apache/inlong/sort/cdc/base/source/enumerator/IncrementalSourceEnumerator.java