code: public function baseTransform()
      {
          parent::baseTransform();
          Requirements::javascript(BETTER_BUTTONS_DIR.'/javascript/gridfield_betterbuttons_delete.js');
  
          return $this
              ->setUseButtonTag(true)
              ->addExtraClass('btn-danger-outline btn-hide-outline font-icon-trash-bin gridfield-better-buttons-delete')
              ->setAttribute("data-toggletext", _t('GridFieldBetterButtons.AREYOUSURE', 'Yes. Delete this item.'))
              ->setAttribute("data-confirmtext", _t('GridFieldDetailForm.CANCELDELETE', 'No. Don\'t delete.'));
      }
docs: Adds the JS, sets up necessary HTML attributes
  @return FormAction