Use refresh instead of visiting the current page

This way it's more obvious what's going on.

Note that, in this case, the expectations were **not** true before
visiting the page, so we aren't fixing a flaky test.

spec/shared/system/flaggable.rb

@@ -34,7 +34,7 @@ shared_examples "flaggable" do |factory_name, admin: false|
       expect(page).not_to have_link "Flag as inappropriate", visible: :all
     end
 
-    visit path
+    refresh
 
     within "##{dom_id(flaggable)} .flag-content" do
       expect(page).to have_link "Unflag", visible: :hidden