Fix Main::Menu locators

Fix the locators to not use a regex
Add requirement

app/views/layouts/header/_default.html.haml

@@ -64,7 +64,7 @@
             .dropdown-menu.dropdown-menu-right
               = render 'layouts/header/help_dropdown'
           - if header_link?(:user_dropdown)
-            %li.nav-item.header-user.dropdown{ data: { track_label: "profile_dropdown", track_event: "click_dropdown" } }
+            %li.nav-item.header-user.dropdown{ data: { track_label: "profile_dropdown", track_event: "click_dropdown", qa_selector: 'user_menu' } }
               = link_to current_user, class: user_dropdown_class, data: { toggle: "dropdown" } do
                 = image_tag avatar_icon_for_user(current_user, 23), width: 23, height: 23, class: "header-user-avatar qa-user-avatar"
                 = sprite_icon('angle-down', css_class: 'caret-down')

qa/qa/page/main/menu.rb

@@ -12,7 +12,7 @@ module QA
         view 'app/views/layouts/header/_default.html.haml' do
           element :navbar, required: true
           element :user_avatar, required: true
-          element :user_menu, '.dropdown-menu' # rubocop:disable QA/ElementWithPattern
+          element :user_menu, required: true
         end
 
         view 'app/views/layouts/nav/_dashboard.html.haml' do
@@ -82,7 +82,7 @@ module QA
         private
 
         def within_top_menu
-          page.within('.qa-navbar') do
+          within_element(:navbar) do
             yield
           end
         end
@@ -91,7 +91,7 @@ module QA
           within_top_menu do
             click_element :user_avatar
 
-            page.within('.dropdown-menu') do
+            within_element(:user_menu) do
               yield
             end
           end