gitlab-ci: test_spm_mpi_dist job is too long on small instance runners, force using large ones

.gitlab/test.yml

@@ -28,6 +28,7 @@ test_spm_seq_shm:
 
 test_spm_mpi_shm:
   extends: .test_script_linux
+  tags: ['ci.inria.fr', 'linux', 'large']
   needs: [build_spm_mpi]
   variables:
     VERSION: mpi
@@ -37,6 +38,7 @@ test_spm_mpi_shm:
 
 test_spm_mpi_dist:
   extends: .test_script_linux
+  tags: ['ci.inria.fr', 'linux', 'large']
   needs: [build_spm_mpi]
   variables:
     VERSION: mpi