CI Update

 Build.Reason:Schedule
 Build.Url:https://apidrop.visualstudio.com/Content%20CI/_build/results?buildId=290967&view=results

Author: VSC-Service-Account

preview/docs-ref-mapping/reference-preview.yml

@@ -498,6 +498,13 @@
       - com.azure.resourcemanager.eventgrid.fluent
       - com.azure.resourcemanager.eventgrid.fluent.models
       - com.azure.resourcemanager.eventgrid.models
+  - name: eventgrid
+    landingPageType: Service
+    items:
+    - name: 'CloudNative CloudEvents with Event Grid '
+      href: ~/docs-ref-services/preview/messaging-eventgrid-cloudnative-cloudevents-readme.md
+      children:
+      - com.azure.messaging.eventgrid.cloudnative.cloudevents
   - name: Face API
     landingPageType: Service
     items: