@Override
  public <StreamMessageType> KafkaOutputDescriptor<StreamMessageType> getOutputDescriptor(String streamId, Serde<StreamMessageType> serde) {
    return new KafkaOutputDescriptor<>(streamId, this, serde);
  }
Constructs a {@link KafkaSystemDescriptor} instance with no system level serde.
Serdes must be provided explicitly at stream level when getting input or output descriptors.

@param systemName name of this system
samza-kafka/src/main/java/org/apache/samza/system/kafka/descriptors/KafkaSystemDescriptor.java