Return result only for the first item to Zabbix (which is what we would

expect as we process a single item at a time)

src/vpoller/helpers/zabbix.py

@@ -102,7 +102,7 @@ def zabbix_item_value(self):
         """
         property_name = self.msg['properties'][0]
 
-        return self.data['result'][property_name]
+        return self.data['result'][0][property_name]
 
     def zabbix_lld_data(self):
         """