Exit loop when cancellation requested

The following manages to create all hitobjects but proceeds to get stuck
in this method:

`dotnet run -- difficulty 1607040 -r:2`

osu.Game/Rulesets/Objects/HitObject.cs

@@ -114,6 +114,8 @@ namespace osu.Game.Rulesets.Objects
             {
                 foreach (HitObject hitObject in nestedHitObjects)
                 {
+                    cancellationToken.ThrowIfCancellationRequested();
+
                     if (hitObject is IHasComboInformation n)
                     {
                         n.ComboIndexBindable.BindTo(hasCombo.ComboIndexBindable);