Quarantine a 'LDAP Group sync' test

Signed-off-by: Rémy Coutable <remy@rymai.me>

qa/qa/specs/features/ee/browser_ui/1_manage/group/group_ldap_sync_spec.rb

@@ -126,7 +126,7 @@ module QA
           Page::Group::Menu.perform(&:click_group_members_item)
         end
 
-        it 'has LDAP users synced' do
+        it 'has LDAP users synced', quarantine: 'https://gitlab.com/gitlab-org/gitlab/issues/196040' do
           verify_users_synced(sync_users)
         end
       end