Updates authorization for lint

What does this MR do?

Updates authorization for ci/lint, and updates specs.

This update is required to conform to the following:

signup_enabled is true and user is auth: OK
signup_enabled is false and user is auth: OK
signup_enabled is true and user is not auth: OK
signup_enabled is false and user is not auth: UNAUTHORIZED

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

Fixes: #321290 (closed)