Simplify test to make it more reliable

For more context, fallow this issue's comment:
https://gitlab.com/gitlab-org/gitlab/commit/
957463991bbb76102e9291baccf060e9f758d73c#note_259513692

qa/qa/specs/features/ee/browser_ui/2_plan/scoped_labels/editing_scoped_labels_spec.rb

@@ -45,16 +45,12 @@ module QA
 
           show.select_all_activities_filter
 
-          initial_labels = "#{initial_label} #{initial_label_multi_colon}"
-          new_labels = "#{new_label_same_scope} #{new_label_same_scope_multi_colon} #{new_label_different_scope_multi_colon} #{new_label_different_scope}"
-
-          expect(page).to have_content("added #{initial_labels}")
-          expect(page).to have_content("added #{new_labels} scoped labels and automatically removed #{initial_labels}")
           expect(show.text_of_labels_block).to have_content(new_label_same_scope)
           expect(show.text_of_labels_block).to have_content(new_label_different_scope)
-          expect(show.text_of_labels_block).not_to have_content(initial_label)
           expect(show.text_of_labels_block).to have_content(new_label_same_scope_multi_colon)
           expect(show.text_of_labels_block).to have_content(new_label_different_scope_multi_colon)
+
+          expect(show.text_of_labels_block).not_to have_content(initial_label)
           expect(show.text_of_labels_block).not_to have_content(initial_label_multi_colon)
         end
       end