Fix specs, policies, and jobs after rebranding of the Testing group

What does this MR do and why?

Rebranding happened with gitlab-com/www-gitlab-com!97760 (merged).

Action items

• (If applicable) Add documentation to the handbook pages for Triage Operations =>
• (If applicable) Identify the affected groups and how to communicate to them:
  • /cc @person_or_group =>
  • Relevant Slack channels =>
  • Engineering week-in-review

Closes #889 (closed).