Add support for the new tooling and `tooling::*` / `feature::*` scoped labels in various Danger checks

What does this MR do?

This is a preparatory step before we deprecate and move away from the backstage label.

Next step will be removing references to ~backstage: #219751 (closed)

See gitlab-org/quality/team-tasks#488 for the overall plan.

Closes #222360 (closed).