Fix CI for EG data-plane (Azure#14171)

* Fix CI for EG data-plane

* Update readme.md

specification/eventgrid/data-plane/readme.md

@@ -19,6 +19,7 @@ In order to automate the mapping of event definition with event type, please fol
 - The description of the new event should include the event type. This is the `eventType` name in an `EventGridEvent` or `type` name in `CloudEvent`. For e.g. `"Schema of the Data property of an EventGridEvent for a Microsoft.Communication.ChatMessageReceived event.` Here `Microsoft.Communication.ChatMessageReceived` is the event name.
 
 A sample valid event definition is shown below:
+~~~ markdown
 ```json
 "AcsChatMessageReceivedEventData": {
   "description": "Schema of the Data property of an EventGridEvent for a Microsoft.Communication.ChatMessageReceived event.",
@@ -35,6 +36,7 @@ A sample valid event definition is shown below:
   }
 }
 ```
+~~~
 
 ---
 ## Getting Started