Ignore some assets on build site on local

[khanhtc1202]

Hi, thanks a lot for the excellent book! Start reading it with great enjoy, but found out when building on local to make some pulls, those asset files have not been ignored yet and a bit annoying.

Description

This pull ignores some assets while building the book site on local.

Change List

• Fix typo error of XXX
• Add description regarding XXX feature
• Resolve error content of XXX

Reference

Please add reference if necessary

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说明

此处详细说明 PR 的动机是什么、解决了什么样的问题。

变化箱单

• 修复了 XXX 的 typo 错误
• 增加了 XXX 相关的说明
• 解决了关于 XXX 的描述性错误

参考文献

如果有请注明