Re-add AutoDevOps Templates spec

What does this MR do?

Add back AutoDevOps Templates spec

Previously, !22254 (merged) broke downstream pipelines when the debase gem was updated. This Merge Request merges the work in, without touching unnecessary gems.

Closes https://gitlab.com/gitlab-org/quality/team-tasks/-/issues/608

Does this MR meet the acceptance criteria?

Conformity

• [-] Changelog entry
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• [-] Database guides
• [-] Separation of EE specific content