Flush the producer after every new record

As the cdc_kafka_producer script is an example, it should flush the
producer after every new record. This should make it easier to see that
events from MaxScale are sent to Kafka.

server/modules/protocol/examples/cdc_kafka_producer.py

@@ -48,6 +48,7 @@ while True:
          data = decoder.raw_decode(rbuf.decode('ascii'))
          rbuf = rbuf[data[1]:]
          producer.send(topic=opts.kafka_topic, value=json.dumps(data[0]).encode())
+         producer.flush()
 
    # JSONDecoder will return a ValueError if a partial JSON object is read
    except ValueError as err:
@@ -57,5 +58,3 @@ while True:
    except Exception as ex:
       print(ex)
       break
-
-producer.flush()