fixed an issue with detecting the visualization enabled state that manifested in usim runs

com.unity.perception/Runtime/GroundTruth/Labelers/CameraLabeler.cs

                 sensorHandle = camera.SensorHandle;
                 Setup();
                 isInitialized = true;
-                m_ShowVisualizations = supportsVisualization && perceptionCamera.showVisualizations;
             }
             catch (Exception)
             {
         internal void InternalCleanup() => Cleanup();
         internal void InternalVisualize() => OnVisualize();
 
-        private bool m_ShowVisualizations = false;
+        bool m_ShowVisualizations;
 
         /// <summary>
         /// Turns on/off the labeler's realtime visualization capability. If a labeler does not support realtime
         {
             get
             {
-                return supportsVisualization && m_ShowVisualizations;
+                if (!supportsVisualization)
+                    return false;
+
+                return perceptionCamera && perceptionCamera.showVisualizations;
             }
             set
             {