remove unused code

Project/Assets/ML-Agents/Examples/SharedAssets/Scripts/OrientationCubeController.cs

 
         public void UpdateOrientation(Vector3 pos, Vector3 dirVector)
         {
-//            var dirVector = target.position - transform.position;
             dirVector.y = 0; //flatten dir on the y. this will only work on level surfaces
             var lookRot =
                 dirVector == Vector3.zero