update UpdateRatingToContent

MediaBrowser.Controller/Entities/Movies/BoxSet.cs

@@ -152,7 +152,7 @@ namespace MediaBrowser.Controller.Entities.Movies
             var currentOfficialRating = OfficialRating;
 
             // Gather all possible ratings
-            var ratings = GetRecursiveChildren(i => i is Movie || i is Series || i is MusicAlbum || i is Game)
+            var ratings = GetLinkedChildren()
                 .Select(i => i.OfficialRating)
                 .Where(i => !string.IsNullOrEmpty(i))
                 .Distinct(StringComparer.OrdinalIgnoreCase)