Update whats-new-overview.md

updated What's new doc for Suspicious API Traffic

Author: Corissalea

concepts/whats-new-overview.md

@@ -19,6 +19,9 @@ For details about previous updates to Microsoft Graph, see [Microsoft Graph what
 
 ## January 2025: New and generally available 
 
+### Identity and access | Identity and sign-in
+- Added riskEventType entry for the Suspicious API Traffic detection for [service principals](/graph/api/resources/serviceprincipalriskdetection?view=graph-rest-1.0&preserve-view=true).
+
 ### Teamwork and communications | Messaging
 
 [Get](/graph/api/chatmessage-get#example-5-get-a-chat-message-with-an--for-everyone) a chat message with an @mention for everyone.