Update protected branches access frontend to include groups.

app/views/projects/protected_branches/_access_level_dropdown.html.haml

@@ -3,7 +3,7 @@
 
 %div{ class: "#{input_basic_name}-container" }
   - if access_levels.present?
-    - dropdown_label = [pluralize(level_frequencies[:role], 'role'), pluralize(level_frequencies[:user], 'user')].to_sentence
+    - dropdown_label = [pluralize(level_frequencies[:role], 'role'), pluralize(level_frequencies[:user], 'user'), pluralize(level_frequencies[:group], 'group')].to_sentence
 
   = dropdown_tag(dropdown_label, options: { toggle_class: "#{toggle_class} js-multiselect", dropdown_class: 'dropdown-menu-user dropdown-menu-selectable', filter: true,
                                  data: { default_label: default_label, preselected_items: access_levels_data(access_levels) } })