Fix compile issues when using cuda 12

CUDA 12 adds a cub::Swap function that creates ambiguity with vtkm::Swap. This happens when a function from the cub namespace is called with an object of a class defined in the vtkm namespace as an argument. If that function has an unqualified call to Swap, it results in ADL being used, causing the templated functions cub::Swap and vtkm::Swap to conflict.

This is a backport of !2960 (merged)

vtkm/exec/cuda/internal/ExecutionPolicy.h

@@ -17,6 +17,7 @@
 #include <vtkm/exec/cuda/internal/ThrustPatches.h>
 VTKM_THIRDPARTY_PRE_INCLUDE
 #include <thrust/execution_policy.h>
+#include <thrust/sort.h>
 #include <thrust/system/cuda/execution_policy.h>
 #include <thrust/system/cuda/memory.h>
 VTKM_THIRDPARTY_POST_INCLUDE