Fix Chinese char brackets in docs

What does this MR do and why?

Related issue #3970 (closed)

修复中文括号导致的格式问题。涉及三个页面

• https://docs.gitlab.cn/jh/administration/settings#general
• https://docs.gitlab.cn/jh/topics/offline/
• https://docs.gitlab.cn/jh/topics/offline/quick_start_guide

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