Update GitLab Workhorse to v8.0.0

What does this MR do?

Updates GitLab Workhorse to v8.0.0

With this change, we can stop sending RepoPath, since workhorse no longer pays any regard to it: gitlab-workhorse!350 (merged)

What are the relevant issue numbers?

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• [-] Documentation created/updated
• Tests added for this feature/bug
• Conforms to the code review guidelines
• Conforms to the merge request performance guidelines
• Conforms to the style guides
• [-] Conforms to the database guides
• [-] Link to e2e tests MR added if this MR has Requires e2e tests label. See the Test Planning Process.
• [-] Security reports checked/validated by reviewer

Closes #55191 (closed)