I tested the webhook event for integration.UserProfileUpdated and it did not trigger on two kinds of profile updates:

• Avatar change
• Profile Signature

It should; they are both options on the Edit Profile page. 

More importantly, these are two ares of moderation risk. There are no alerts for when users update either of these fields that display prominently across the community UI. 

Adding them to the payload, or providing new a webhook event for each would allow admins to subscribe to updates and create their own alerts, monitoring to ensure nothing inappropriate is being displayed on profiles or posts.