ci: one more try to fix it

.gitlab-ci.yml

@@ -13,7 +13,8 @@ build:
   script:
     - opam repo add verimag-sync-repo "http://www-verimag.imag.fr/DIST-TOOLS/SYNCHRONE/test/opam-repository"
     - opam update
-    - opam install depext ./lutin.opam ./bddrand.opam  ./ezdl.opam  ./gbddml.opam ./polka.opam
+    - sudo apt update
+    - opam depext lutin 
     - opam install --deps-only ./lutin.opam ./bddrand.opam  ./ezdl.opam  ./gbddml.opam ./polka.opam
     - make
     - make install