Add setting to the top-level group namespace to allow owners to disable runner registration for sub-groups and projects

Overview

In 15.5 we introduced settings in Admin Area > Settings > CI/CD > Runners for disabling runner registration for groups and projects. This option is not available to customers on GitLab.com who need a simple mechanism to prevent runner sprawl.

Proposal

• Add the option to disable runner registration to top-level group namespaces.

Open Questions

• For Self-Managed should option be hidden by default behind a feature flag?

Available Tier

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