workflow: Actually using the KOKKOS_VERSION variable

Currently the version is still hardcoded for each job in at2.yml
Now switching to use the control variable so all the jobs can be
in sync and switched at once for easier maintenance.

Signed-off-by: Luc Berger-Vergiat <lberge@sandia.gov>

.github/workflows/at2.yml

@@ -25,20 +25,20 @@ jobs:
   mi210:
     uses: ./.github/workflows/mi210.yml
     with:
-      kokkos_version: 4.4.01
+      kokkos_version: ${{ env.KOKKOS_VERSION }}
   h100:
     uses: ./.github/workflows/h100.yml
     with:
-      kokkos_version: 4.4.01
+      kokkos_version: ${{ env.KOKKOS_VERSION }}
   bdw:
     uses: ./.github/workflows/bdw.yml
     with:
-      kokkos_version: 4.4.01
+      kokkos_version: ${{ env.KOKKOS_VERSION }}
   spr:
     uses: ./.github/workflows/spr.yml
     with:
-      kokkos_version: 4.4.01
+      kokkos_version: ${{ env.KOKKOS_VERSION }}
   volta70:
     uses: ./.github/workflows/volta70.yml
     with:
-      kokkos_version: 4.4.01
+      kokkos_version: ${{ env.KOKKOS_VERSION }}