fix the docker host for deploy

.gitlab-ci.yml

@@ -32,6 +32,8 @@ deploy_dev:
   stage: deploy
   tags: 
     - deploy_dev
+  variables:
+    DOCKER_HOST: tcp://localhost:2375/
   script:
     - echo "deploying dev"
     - docker login -u $DOCKERHUBUSER -p $DOCKERHUBPASSWORD docker.io