ci(tests): Fix exclusion of tests on stable

.gitlab-ci.yml

@@ -246,7 +246,7 @@ test_front:
     - if: $CI_PIPELINE_SOURCE == "merge_request_event" || $CI_PIPELINE_SOURCE == "push"
       changes:
         - front/**/*
-    - if: $CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH
+    - if: $CI_COMMIT_BRANCH == "develop" || $CI_COMMIT_BRANCH == "stable"
       when: always
 
 build_docs: