Added new event for Lookup

Author: KumarVivek

powerapps-docs/developer/model-driven-apps/clientapi/reference/events.md

@@ -45,8 +45,10 @@ Events occur in Custom Engagement forms and grids whenever a form or grid loads,
 - [PostSearch](events/postsearch.md)
 
 ## Lookup control event
+- [OnLookupTagClick](events/onlookuptagclick.md)
 - [PreSearch](events/presearch.md)
 
+
 ## Process events
 - [OnProcessStatusChange](events/onprocessstatuschange.md)
 - [OnStageChange](events/onstagechange.md)