docs: fix some problems in docs/kitex/Tutorials/basic-feature/message_type

[zhu-mi-shan]

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修复了docs/kitex/Tutorials/basic-feature/message_type文档的一些问题。

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en: The fixed problems include package reference problems, parameter problems, directory structure problems, parallel program problems...

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[cqqqq777]

语法上的错误可以修改，但是有些业务处理的的方式个人觉得没必要添加，此处应该只是展示各种消息类型的基本使用框架