@Override
    public ChangelogMode getChangelogMode() {
        return changelogMode;
    }
Usually it is the same as the valueDecodingFormat, but use a different naming to show that it
is used to list all the format metadata keys.
inlong-sort/sort-flink/sort-flink-v1.15/sort-connectors/pulsar/src/main/java/org/apache/inlong/sort/pulsar/table/PulsarTableSource.java