关于bot.broadcast传参问题

以前根据文档所述传参是不存在问题.
目前传参方法有变,需要一个示例附带修改下文档的说明
以下是文档链接
https://koishi.chat/api/core/bot.html#bot-broadcast

Open the linked bot.broadcast documentation page first and compare its parameter description and example with the current calling behavior described in the issue. Update the example and explanatory text to match the current method, then verify the rendered page clearly documents the required arguments.

Written by the indexing model from the issue text.