Minor producer bug fix

Change-Id: I09aa020a5e257fe68eb222f61862260d48f191e3
Signed-off-by: Helena McGough <helena.mcgough@intel.com>
diff --git a/osm_mon/core/message_bus/producer.py b/osm_mon/core/message_bus/producer.py
index bccdd4c..85b608a 100755
--- a/osm_mon/core/message_bus/producer.py
+++ b/osm_mon/core/message_bus/producer.py
@@ -57,7 +57,7 @@
 
         self.producer = kaf(
             key_serializer=str.encode,
-            value_serializer=lambda v: json.dumps(v).str.encode,
+            value_serializer=str.encode,
             bootstrap_servers=broker, api_version=(0, 10))
 
     def publish(self, key, value, topic=None):