Merge branch 'port-6539-extract-ee-specific-code' into 'master'

Extract EE specific files/lines for quick actions tests

See merge request gitlab-org/gitlab-ce!26872

spec/services/notes/quick_actions_service_spec.rb

@@ -185,6 +185,7 @@ describe Notes::QuickActionsService do
       end
 
       before do
+        stub_licensed_features(multiple_issue_assignees: false)
         project.add_maintainer(maintainer)
         project.add_maintainer(assignee)
       end