daat2.x以上版本安装报错，应该是插件停留在1.x版本

[Longfei-Yan]

PHP版本：PHP 7.4.29 (cli) (built: Apr 21 2022 10:16:17) ( NTS )
Laravel版本：6
Dcat版本：v2.2.0-beta

报错信息如下：

Package swiftmailer/swiftmailer is abandoned, you should avoid using it. Use symfony/mailer instead.
Generating optimized autoload files

post-autoload-dump: Illuminate\Foundation\ComposerScripts::postAutoloadDump
PHP Fatal error: Uncaught Error: Call to undefined method Dcat\Admin\Admin::extend() in /home/longfei/www/test_larave/vendor/dcat-admin-extension/grid-sortable/src/bootstrap.php:4