Fix error 500 on Runners page.

What does this MR do?

Fixes error 500 on Runners page (ActionView::Template::Error (Missing partial kaminari/_paginator)

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

Why was this MR needed?

What are the relevant issue numbers?

No GitLab issue; originally reported downstream: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=819903

Screenshots (if relevant)

N/A

Does this MR meet the acceptance criteria?

• CHANGELOG entry added
• Documentation created/updated
• API support added
• 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