Fix issue when drag begins before dragula is initialized

lib/capybara/spec/session/node_spec.rb

@@ -446,7 +446,7 @@ Capybara::SpecHelper.spec 'node' do
 
     it 'should work with Dragula' do
       @session.visit('/with_dragula')
-      @session.within(:css, '#sortable') do
+      @session.within(:css, '#sortable.ready') do
         src = @session.find('div', text: 'Item 1')
         target = @session.find('div', text: 'Item 3')
         src.drag_to target

lib/capybara/spec/views/with_dragula.erb

@@ -15,7 +15,9 @@
     </div>
     <script src="https://cdnjs.cloudflare.com/ajax/libs/dragula/3.7.2/dragula.js" type="text/javascript"></script>
     <script>
-      dragula([document.getElementById("sortable")]);
+      let container = document.getElementById("sortable");
+      dragula([container]);
+      container.className = "ready"
     </script>
   </body>
 </html>