Add commit ref name to dev build as tag

.gitlab-ci.yml

@@ -209,8 +209,8 @@ build_backend:
     - docker login -u $CI_REGISTRY_USER -p $CI_REGISTRY_PASSWORD $CI_REGISTRY
   script:
     - cd api
-    - docker build -t $CI_REGISTRY_IMAGE .
-    - docker push $CI_REGISTRY_IMAGE
+    - docker build -t $CI_REGISTRY_IMAGE:$CI_COMMIT_REF_NAME .
+    - docker push $CI_REGISTRY_IMAGE:$CI_COMMIT_REF_NAME
   tags:
     - docker-build