Fix file links on project page Files view

What does this MR do?

Fix the project show page when the default view is set to Files so that the links work.

Are there points in the code the reviewer needs to double check?

I can't figure out what caused this to break 😕

What are the relevant issue numbers?

Closes https://gitlab.com/gitlab-com/support-forum/issues/959.

Does this MR meet the acceptance criteria?

• CHANGELOG entry added
• Documentation created/updated (N/A)
• API support added (N/A)
• Tests
  • Added for this feature/bug
  • All builds are passing
• Conform by the style guides
• Branch has no merge conflicts with master (if you do - rebase it please)
• Squashed related commits together