Update the minimum Kokkos required to 3.7

This was suggested by a developer on the Kokkos team.

CMake/VTKmDeviceAdapters.cmake

@@ -322,7 +322,7 @@ endfunction()
 if(VTKm_ENABLE_KOKKOS AND NOT TARGET vtkm_kokkos)
   cmake_minimum_required(VERSION 3.13 FATAL_ERROR)
 
-  find_package(Kokkos REQUIRED)
+  find_package(Kokkos 3.7 REQUIRED)
 
   # We must empty this property for every kokkos backend device since it
   # contains a generator expresion which breaks some of our users builds.

README.md

@@ -76,6 +76,8 @@ VTK-m Requires:
 
 Optional dependencies are:
 
+  + Kokkos Device Adapter
+      + [Kokkos](https://kokkos.github.io/) 3.7+
   + CUDA Device Adapter
       + [Cuda Toolkit 9.2, >= 10.2](https://developer.nvidia.com/cuda-toolkit)
       + Note CUDA >= 10.2 is required on Windows

docs/changelog/require-kokkos-3-7.md

@@ -0,0 +1,4 @@
+# Require Kokkos 3.7
+
+The minimum version of Kokkos supported is now set to Kokkos 3.7. This is
+to synchronize with the development of the Kokkos team.