Fix collapsing of milestones and labels items

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

@@ -52,6 +52,7 @@
     = nav_link(controller: :milestones) do
       = link_to project_milestones_path(@project), title: 'Milestones' do
         %i.fa.fa-clock-o
+        %span
           Milestones
 
     - if project_nav_tab? :issues
@@ -74,6 +75,7 @@
     = nav_link(controller: :labels) do
       = link_to project_labels_path(@project), title: 'Labels' do
         %i.fa.fa-tags
+        %span
           Labels
 
     - if project_nav_tab? :wiki