Update gitlab-runner/config.toml for EKS based runners with GitLab Cloud

We are using GitLab Cloud with a private repository and private runners running on EKS. We run into several issues related to tuning and configuration that could be addressed by updating the gitlab-runner/config.toml file. Unfortunately while GitLab cloud makes it relatively easy to connect to EKS and deploy a runner, there is no option that I could find either in the GUI or the official documentation to update the TOML settings such as ‘concurrent’, ‘cache_dir’ or ‘output_limit’.

This is currently a show stopper for us to be able to use GitLab.