Add danger rule and plugin for pipeline status

What does this MR do and why?

Re: Step 3 in Notify failed master pipeline status in merge r... (gitlab-org/quality/engineering-productivity/team#453 - closed)

MR acceptance checklist

Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

Screenshots or screen recordings

I used Draft: Test #148451 (!148598 - closed) to verify the output of the danger message.

Scenario 1: master pipeline status contains a failed rubocop job:

✅ danger-review job stacktrace

Scenario 2: master pipeline status page contains invalid JSON:

✅ danger-review job stacktrace

Scenario 3: master pipeline status page does not exist:

✅ danger-review job stacktrace

Scenario 4: all master pipeline jobs passed:

✅ danger-review job stacktrace

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.