Update functions-bindings-event-hubs-trigger.md

updated decorator name to event_hub_message_trigger from cosmos_db_trigger

Author: asanjabi

includes/functions-bindings-event-hubs-trigger.md

@@ -366,7 +366,7 @@ In [C# class libraries](../articles/azure-functions/functions-dotnet-class-libra
 
 _Applies only to the Python v2 programming model._
 
-For Python v2 functions defined using a decorator, the following properties on the `cosmos_db_trigger`:
+For Python v2 functions defined using a decorator, the following properties on the `event_hub_message_trigger`:
 
 | Property    | Description |
 |-------------|-----------------------------|