Prevent project owners/maintainers from changing runner registration
As a GitLab administrator I want to provide runners (as a service) to global development teams, however due to the scale of SCM adoption our initial "Shared runners" service will not have the capacity to meet the demands of all teams. So we would like to selectively register runners to projects/groups to control adoption while we work to add capacity. The problem is that project owners/maintainers can edit runners (active, protected, locked, run untagged jobs) and enable them on other projects which effectively makes them more widely available than we want or have the capacity to serve.
Create an option to lock a runner's registration so that project owners/maintainers cannot register the runner elsewhere. Only a GitLab admin would be able to register the runner to new projects (via the API).