Use new Random.Shared instead of creating new instances

Emby.Server.Implementations/Dto/DtoService.cs

@@ -420,7 +420,7 @@ namespace Emby.Server.Implementations.Dto
             // Just return something so that apps that are expecting a value won't think the folders are empty
             if (folder is ICollectionFolder || folder is UserView)
             {
-                return new Random().Next(1, 10);
+                return Random.Shared.Next(1, 10);
             }
 
             return folder.GetChildCount(user);