[mob][photos] Refresh people section on people changed event

mobile/lib/models/search/search_types.dart

@@ -293,6 +293,8 @@ extension SectionTypeExtensions on SectionType {
     switch (this) {
       case SectionType.location:
         return [Bus.instance.on<LocationTagUpdatedEvent>()];
+      case SectionType.face:
+        return [Bus.instance.on<PeopleChangedEvent>()];
       default:
         return [];
     }