revise spec to account for phone setup controller ability to show errors

spec/controllers/users/phone_setup_controller_spec.rb

@@ -94,7 +94,7 @@
       }
 
       expect(response).to render_template(:index)
-      expect(flash[:error]).to be_blank
+      expect(flash[:error]).not_to be_blank
     end
 
     context 'with recaptcha error' do