add 72M step model

Project/Assets/ML-Agents/Examples/Soccer/Scripts/AgentSoccer.cs

             {
                 sensor.AddObservation(CurrentRayAngleLerp);
                 sensor.AddObservation(CurrentSpherecastRadiusLerp);
-                sensor.AddObservation(GameController.LocalBallVelocity);
-                sensor.AddObservation(GameController.LocalBallPositionNormalizedToFieldSize);
+                // sensor.AddObservation(GameController.LocalBallVelocity);
+                // sensor.AddObservation(GameController.LocalBallPositionNormalizedToFieldSize);
             }
         }
     }

Project/Assets/ML-Agents/Examples/Soccer/TFModels/SoccerTwos-72910960.onnx.meta

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