版本：
文件：
- https://cdn.bootcdn.net/ajax/libs/jquery-once/2.3.0/jquery.once.js
- https://cdn.bootcdn.net/ajax/libs/jquery-once/2.3.0/jquery.once.min.js
- https://cdn.bootcdn.net/ajax/libs/jquery-once/2.3.0/jquery.once.min.js.map