Update .gitlab-ci.yml file

.gitlab-ci.yml

-default:
-  tags:
-    - cloud
-    - docker
+image: docker:20.10.16
 
-build_image:
+variables:
+  # When you use the dind service, you must instruct Docker to talk with
+  # the daemon started inside of the service. The daemon is available
+  # with a network connection instead of the default
+  # /var/run/docker.sock socket. Docker 19.03 does this automatically
+  # by setting the DOCKER_HOST in
+  # https://github.com/docker-library/docker/blob/d45051476babc297257df490d22cbd806f1b11e4/19.03/docker-entrypoint.sh#L23-L29
+  #
+  # The 'docker' hostname is the alias of the service container as described at
+  # https://docs.gitlab.com/ee/ci/services/#accessing-the-services.
+  #
+  # Specify to Docker where to create the certificates. Docker
+  # creates them automatically on boot, and creates
+  # `/certs/client` to share between the service and job
+  # container, thanks to volume mount from config.toml
+  DOCKER_TLS_CERTDIR: "/certs"
+
+services:
+  - docker:20.10.16-dind
+
+build:
   stage: build
-  image: docker:dind
   before_script:
     - docker info
     - docker login -u $CI_REGISTRY_USER -p $CI_REGISTRY_PASSWORD $CI_REGISTRY