Globally-defined `image`,`services` are deprecated

contents of https://docs.gitlab.com/ee/ci/examples/laravel_with_gitlab_and_envoy/index.html#setting-up-gitlab-cicd should be updated to the latest specs of .gitlab-ci.yml (see https://docs.gitlab.com/ee/ci/yaml/README.html#globally-defined-image-services-cache-before_script-after_script)