revert(route/xiaohongshu): add current time as pubDate

[KawausoJyou]

Reason for revert: The change did not meet the expected behavior or caused issues.

Involved Issue / 该 PR 相关 Issue

Close #17602

Example for the Proposed Route(s) / 路由地址示例

/xiaohongshu/user/:user_id/notes/fulltext
/xiaohongshu/user/:user_id/:category

New RSS Route Checklist / 新 RSS 路由检查表

• [ ] New Route / 新的路由
  • [ ] Follows Script Standard / 跟随 路由规范
• [ ] Anti-bot or rate limit / 反爬/频率限制
  • [ ] If yes, do your code reflect this sign? / 如果有, 是否有对应的措施?
• [ ] Date and time / 日期和时间
  • [ ] Parsed / 可以解析
  • [ ] Correct time zone / 时区正确
• [ ] New package added / 添加了新的包
• [ ] Puppeteer

Note / 说明