Update win-CI to source Intel-MPI.bat.

Author: vehre

.github/workflows/win-ci.yml

@@ -36,6 +36,7 @@ jobs:
     - name: MPI info
       run: |
         echo "${{ steps.setup-mpi.outputs.mpi }}"
+        ${I_MPI_ROOT}/bin/vars.bat
         set -o verbose
         # mpiexec -help
         type mpiexec