Cleanup after rebase.

com.unity.perception/Tests/Editor/PerceptionCameraEditorTests.cs

 using System;
 using System.Collections;
-using System.Collections.Generic;
-using Unity.Collections;
-using UnityEngine.Perception;
-using UnityEngine.Perception.Sensors;
+using UnityEngine.Perception.GroundTruth;
+using UnityEngine.SceneManagement;
 using UnityEngine.TestTools;
 
 namespace EditorTests
         [UnityTest]
         public IEnumerator EditorPause_DoesNotLogErrors()
         {
-            int sceneCount = EditorSceneManager.sceneCount;
+            int sceneCount = SceneManager.sceneCount;
-                EditorSceneManager.CloseScene(EditorSceneManager.GetSceneAt(i), true);
+                EditorSceneManager.CloseScene(SceneManager.GetSceneAt(i), true);
             }
 
             EditorSceneManager.NewScene(NewSceneSetup.EmptyScene);
             yield return new ExitPlayMode();
         }
 
-        static GameObject SetupCamera(LabelingConfiguration labelingConfiguration)
+        static void SetupCamera(LabelingConfiguration labelingConfiguration)
         {
             var cameraObject = new GameObject();
             cameraObject.SetActive(false);
             perceptionCamera.produceObjectCountAnnotations = true;
 
             cameraObject.SetActive(true);
-            return cameraObject;
         }
     }
 }

com.unity.perception/Tests/Runtime/GroundTruthTests/BoundingBox2DTests.cs

 using System;
 using System.Collections;
 using System.Collections.Generic;
-using System.Linq;
-using UnityEngine.Experimental.Rendering;
-using UnityEngine.Perception;
 using UnityEngine.Perception.GroundTruth;
 using UnityEngine.TestTools;
 

com.unity.perception/Tests/Runtime/GroundTruthTests/GroundTruthTestBase.cs

 using System.Collections.Generic;
 using System.IO;
 using NUnit.Framework;
-using Unity.Simulation;
 using UnityEngine;
 using UnityEngine.Perception.GroundTruth;
 using Object = UnityEngine.Object;

com.unity.perception/Tests/Runtime/GroundTruthTests/PerceptionCameraIntegrationTests.cs

 using System.Collections.Generic;
 using System.IO;
 using NUnit.Framework;
-using Unity.Collections;
-using UnityEngine.Perception;
-using UnityEngine.Perception.Sensors;
+using UnityEngine.Perception.GroundTruth;
-using Object = UnityEngine.Object;
 
 namespace GroundTruthTests
 {
               ""height"": {Screen.height / 2:F1}
             }}";
             var labelingConfiguration = CreateLabelingConfiguration();
-            var camera = SetupCamera(labelingConfiguration, pc =>
+            SetupCamera(labelingConfiguration, pc =>
             {
                 pc.produceBoundingBoxAnnotations = true;
             });