public TransactionBoundary transactionBoundary() {
        return transactionBoundary;
    }
Returns an enriched {@link ConfigDef} building upon the {@code ConfigDef}, using the current configuration specified in {@code props} as an input.

@param baseConfigDef the base configuration definition to be enriched
@param props the non parsed configuration properties
@return the enriched configuration definition
connect/runtime/src/main/java/org/apache/kafka/connect/runtime/SourceConnectorConfig.java