[Port] [6000.0] Fix small GPUResidentDrawer bugs

Fixes some small bugs:
* https://jira.unity3d.com/browse/UUM-83561
* https://jira.unity3d.com/browse/UUM-83578
* https://jira.unity3d.com/browse/UUM-84509

Author: svc-reach-platform-support

Packages/com.unity.render-pipelines.core/Runtime/GPUDriven/GPUResidentDrawer.Validator.cs

@@ -42,7 +42,7 @@ internal static bool IsProjectSupported(out string message, out LogType severity
 #if UNITY_EDITOR
             // Check the build target is supported by checking the depth downscale kernel (which has an only_renderers pragma) is present
             var resources = GraphicsSettings.GetRenderPipelineSettings<GPUResidentDrawerResources>();
-            if (!resources.occluderDepthPyramidKernels.HasKernel("OccluderDepthDownscale"))
+            if (!(resources.occluderDepthPyramidKernels && resources.occluderDepthPyramidKernels.HasKernel("OccluderDepthDownscale")))
             {
                 severity = LogType.Warning;
                 message  = Strings.kernelNotPresent;

Packages/com.unity.render-pipelines.core/Runtime/GPUDriven/InstanceData/InstanceData.cs

@@ -483,8 +483,11 @@ public void Remove(SharedInstanceHandle instance)
 
             instances[index] = instances[lastIndex];
             rendererGroupIDs[index] = rendererGroupIDs[lastIndex];
+
             materialIDArrays[index].Dispose();
             materialIDArrays[index] = materialIDArrays[lastIndex];
+            materialIDArrays[lastIndex] = default;
+
             meshIDs[index] = meshIDs[lastIndex];
             localAABBs[index] = localAABBs[lastIndex];
             flags[index] = flags[lastIndex];

Packages/com.unity.render-pipelines.core/Runtime/GPUDriven/Utilities/ParallelSortExtensions.cs

@@ -94,11 +94,11 @@ static void Swap(ref NativeArray<int> a, ref NativeArray<int> b)
                     Swap(ref arraySource, ref arrayDest);
                 }
 
-                supportArray.Dispose();
-                counter.Dispose();
-                buckets.Dispose();
-                indices.Dispose();
-                indicesSum.Dispose();
+                supportArray.Dispose(jobHandle);
+                counter.Dispose(jobHandle);
+                buckets.Dispose(jobHandle);
+                indices.Dispose(jobHandle);
+                indicesSum.Dispose(jobHandle);
             }
             else
             {