Fix stype

Author: Ashish944

Diff for: app/views/light/newsletters/_top_navbar.html.haml

@@ -1,8 +1,8 @@
 = nav_bar :brand => 'Newsletters', :responsive => true, :static => :top, :fluid => :true do
   = menu_group do
     = menu_item 'Add Newsletter', new_newsletter_path
-    = menu_item 'Opt in letters', newsletters_path(type: "Opt-In Letter")
-    = menu_item 'Opt out letters', newsletters_path(type: "Opt-Out Letter")
+    = menu_item 'Opt in letters', newsletters_path(type: 'Opt-In Letter')
+    = menu_item 'Opt out letters', newsletters_path(type: 'Opt-Out Letter')
     = drop_down 'Add Users' do
       = menu_item 'Add Manually', new_user_path
       = menu_item 'Import Opt-in Users', users_import_path