fix: correct typo comitting → committing in checklist

[xiajixi76-beep]

描述

修正了拼写错误：comitting → committing

修改的文件

• guides/your-first-pr-checklist.md

Closes #5

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这是我的第一个PR！感谢这个教学项目！ 😊

[github-actions]

Hi! This looks like your first pull request to this repo — welcome. 🎉

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