Added sub-nav to new group sidebar

Closes #35140

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

@@ -55,7 +55,22 @@
         %span
           Members
     - if current_user && can?(current_user, :admin_group, @group)
-      = nav_link(path: %w[groups#projects groups#edit]) do
+      = nav_link(path: %w[groups#projects groups#edit ci_cd#show]) do
         = link_to edit_group_path(@group), title: 'Settings' do
           %span
             Settings
+        %ul.sidebar-sub-level-items
+          = nav_link(path: 'groups#edit') do
+            = link_to edit_group_path(@group), title: 'General' do
+              %span
+                General
+
+          = nav_link(path: 'groups#projects') do
+            = link_to projects_group_path(@group), title: 'Projects' do
+              %span
+                Projects
+
+          = nav_link(controller: :ci_cd) do
+            = link_to group_settings_ci_cd_path(@group), title: 'Pipelines' do
+              %span
+                Pipelines