erp5_core: render the gadget_button_maximize.html gadget

product/ERP5/bootstrap/erp5_core/SkinTemplateItem/portal_skins/erp5_core/gadget_editor.js.js

@@ -148,6 +148,8 @@
                   scope: 'maximize',
                   element: div_max,
                   sandbox: 'public'
+                }).push(function (button_maximize_gadget) {
+                  return button_maximize_gadget.render();
                 });
               }, function (error) {
               // Check Acquisition, old erp5 ui don't have triggerMaximize