Fix external issue tracker "Issues" link leading to 404s

What does this MR do?

This MR fixes the redirection to the wrong URL when using an external issue tracker, such as JIRA or Redmine. a70431f8 modified the behavior to link to the external issue tracker issues URL instead of the project path URL. This restores the previous behavior.

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

Is the project URL really the intended target?

Why was this MR needed?

The issues URL often has :id associated with it for linking mentioned issues. For external issue trackers, the project page is the intended taret.

What are the relevant issue numbers?

#21252 (closed), #21402 (closed)

Does this MR meet the acceptance criteria?

• CHANGELOG entry 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