Fix sorting issues/mrs by votes on the groups page
Closes#14394
The `non_archived` scope applied here https://gitlab.com/gitlab-org/gitlab-ce/blob/master/app/controllers/concerns/issues_action.rb#L5 overrides the previous `ORDER BY` applied inside the IssuesFinder, with the default scope of the Project model, resulting in SQL errors.
```ruby
Issue.reorder(created_at: :desc).joins(:project).to_sql
=> "SELECT issues.*
FROM issues INNER JOIN projects ON projects.id = issues.project_id
ORDER BY issues.created_at DESC"
Issue.reorder(created_at: :desc).joins(:project).merge(Project.non_archived).to_sql
=> "SELECT issues.*
FROM issues INNER JOIN projects ON projects.id = issues.project_id
WHERE projects.archived = 'f'
ORDER BY projects.id DESC"
Issue.reorder(created_at: :desc).joins(:project).merge(Project.non_archived.only(:where)).to_sql
=> "SELECT issues.*
FROM issues INNER JOIN projects ON projects.id = issues.project_id
WHERE projects.archived = 'f'
ORDER BY issues.created_at DESC"
```
/cc @yorickpeterse
See merge request !3333
703f7c5d57