Fix exceptions in non-development players on some graphics backends (#66)

TestProjects/PerceptionURP/Assets/Scenes/SampleScene.unity

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com.unity.perception/Runtime/GroundTruth/PerceptionCamera.cs

         [SerializeField]
         public bool showVisualizations = true;
 
-        bool m_ShowingVisualizations;
+        bool m_ShowingVisualizations = false;
 
         /// <summary>
         /// The <see cref="SensorHandle"/> associated with this camera. Use this to report additional annotations and metrics at runtime.
             SetupInstanceSegmentation();
             var cam = GetComponent<Camera>();
 
-#if UNITY_EDITOR || DEVELOPMENT_BUILD
-#endif
+
 
             DatasetCapture.SimulationEnding += OnSimulationEnding;
         }
 
         void SetupVisualizationCamera(Camera cam)
         {
+#if !UNITY_EDITOR && !DEVELOPMENT_BUILD
+            showVisualizations = false;
+#else
+
             var visualizationAllowed = s_VisualizedPerceptionCamera == null;
 
             if (!visualizationAllowed && showVisualizations)
             s_VisualizedPerceptionCamera = this;
 
             hudPanel = gameObject.AddComponent<HUDPanel>();
+#endif
         }
 
         void CheckForRendererFeature(ScriptableRenderContext context, Camera camera)