Read complete lines with Kafka producer

There's no need to process the JSON twice as the Kafka producer is
expected to be used with the Python CDC client which already splits the
JSON with newlines.

server/modules/protocol/examples/cdc_kafka_producer.py

@@ -36,7 +36,7 @@ producer = KafkaProducer(bootstrap_servers=[opts.kafka_broker])
 
 while True:
    try:
-      buf = sys.stdin.read(128)
+      buf = sys.stdin.readline()
 
       if len(buf) == 0:
          break