Link to path, not URL, from sidebar

app/views/layouts/nav/sidebar/_project.html.haml

@@ -135,7 +135,7 @@
 
             - if EE::Gitlab::ServiceDesk.enabled?(project: @project)
               = nav_link(controller: :issues, action: :service_desk ) do
-                = link_to service_desk_project_issues_url(@project), title: 'Service Desk' do
+                = link_to service_desk_project_issues_path(@project), title: 'Service Desk' do
                   %span Service Desk
 
             = nav_link(controller: :milestones) do