MM-24386/MM-24465 Enable link previews and full push notifications by default (#14565)

* MM-24386 Update default push notification contents to full

* MM-24465 Enable link previews by default

* Fix a unit test relying on the old default

model/config.go

@@ -369,7 +369,7 @@ func (s *ServiceSettings) SetDefaults(isUpdate bool) {
 	}
 
 	if s.EnableLinkPreviews == nil {
-		s.EnableLinkPreviews = NewBool(false)
+		s.EnableLinkPreviews = NewBool(true)
 	}
 
 	if s.EnableTesting == nil {
@@ -1459,7 +1459,7 @@ func (s *EmailSettings) SetDefaults(isUpdate bool) {
 	}
 
 	if s.PushNotificationContents == nil {
-		s.PushNotificationContents = NewString(GENERIC_NOTIFICATION)
+		s.PushNotificationContents = NewString(FULL_NOTIFICATION)
 	}
 
 	if s.EnableEmailBatching == nil {