Remove old docker helper image commands
Overview
We have some bash scripts specifically gitlab-runner-cache and gitlab-runner-service that the helper image uses. Since we need to have the same behavior between Windows and Linux we ported the bash scripts into Go as part of the gitlab-runner-helper binary. This results in a change of the command from gitlab-runner-cache to gitlab-runner-helper cache init & gitlab-runner-service to gitlab-runner-helper health-check. If a user specified helper_image inside of the runner configuration it might lead into a breaking change if a user updated the runner to %11.9 and has an old image of gitlab/gitlab-runner-helper specified. The new commands are used automatically if the user hasn't specified a helper_image. The removal of the old commands will be done in %12.0, please follow #3473 (closed) for a full list of deprecated features.
How to upgrade
If you are using an old image, you can download the latest helper image from https://hub.docker.com/r/gitlab/gitlab-runner-helper/tags/ or https://gitlab-runner-downloads.s3.amazonaws.com/v11.9.0/index.html and enable the feature flag FF_DOCKER_HELPER_IMAGE_V2 this will start using the new API.