This is a hot-fix that prevents using the `DOCKER_AUTH_CONFIG` env-var
as a credential helper when running in Gitlab CI (determined by
`GITLAB_CI` environment variable).
An explicit setting controlling this behavior is available through the
`auth_config_order` feature flag in the Docker CLI config (and
`DOCKER_AUTH_ORDER` environment variable that takes precedence over the
feature flag value).
It accepts a comma separated "config" and "env" strings which determine
the order.
Currently, possible values are:
- "config,env" - prefer the auth from config.json first
- "env,config" - prefer the auth from `DOCKER_AUTH_CONFIG`
```json ~/.docker/config.json
{
 ...,
 "features": {
 "auth_config_order": "config,env"
 }
}
```
Signed-off-by: Paweł Gronowski <pawel.gronowski@docker.com>