style: Cancel the io/outil libraries used in the project and switch to using native methods of os and io libraries

[miajio]

What type of PR is this?

style

Check the PR title.

Cancel the io/outil libraries used in the project and switch to using native methods of os and io libraries

(Optional) Translate the PR title into Chinese.

取消项目中使用的io/ioutil库, 变更为使用os及io库原生方法

(Optional) More detailed description for this PR(en: English/zh: Chinese).

en: Cancel the io/outil libraries used in the project and switch to using native methods of os and io libraries
zh(optional): 取消项目中使用的io/ioutil库, 变更为使用os及io库原生方法

(Optional) Which issue(s) this PR fixes:

unknown

(Optional) The PR that updates user documentation:

unknown

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[GuangmingLuo]

@miajio PR title 使用英文，格式参考其它已经合并的 PR；点击上述链接签署下 CLA 协议。

[GuangmingLuo]

@miajio 还没有签署 CLA