Test config ci: need to try ssh access to gitlab from the runner

.gitlab-ci.yml

-
 stages:
   - build
   - test
@@ -6,6 +5,7 @@ stages:
 build:
   stage: build
   script:
+    - ssh -vvv git@gitlab.inria.fr
     - git submodule init
     - git submodule update
     - mkdir build