Change dind configuratino to 18.09

.gitlab-ci.yml

@@ -22,7 +22,7 @@ build-image:
   image: docker:latest
   stage: build
   services:
-    - name: docker:dind
+    - docker:18.09-dind
   script:
     - source .env.update
     - if [ "$NEED_UPDATE" = false ]; then exit 0; fi
@@ -36,7 +36,7 @@ build-image:
     - echo $NEW_URL
     - sed -i "/wget/c$NEW_URL" docker/assets/download-package
     - cd docker
-    - echo "nameserver 127.0.0.11" > /etc/resolv.conf
     - docker build -t git.halia.dev/athens-school/gitlab:testing .
   variables:
-    DOCKER_TLS_CERTDIR: ""
+    DOCKER_HOST: tcp://docker:2375/
+    DOCKER_DRIVER: overlay2