Remove unnecessary test expectation

See https://bit.ly/2KioAMa

qa/qa/specs/features/browser_ui/2_plan/ee_epic/promote_issue_to_epic_spec.rb

@@ -32,8 +32,6 @@ module QA
           # confidential information)' from being shown, which may cause the click not
           # to work properly.
           show.comment('/promote ')
-
-          expect(show).to have_content("promoted to epic")
         end
 
         group.visit!