chore: improve less variable @form-item-margin-bottom

[yoyo837]

🤔 This is a ...

• New feature
• Bug fix
• Site / document update
• Component style update
• TypeScript definition update
• Refactoring
• Code style optimization
• Test Case
• Branch merge
• Other (about what?)

🔗 Related issue link

#21302 (comment)

💡 Background and solution

📝 Changelog

Language	Changelog
🇺🇸 English	Fix Form fields shake when @form-item-margin-bottom is customize and switching the validing info.
🇨🇳 Chinese	修复 Form 自定义 @form-item-margin-bottom 变量时表单校验抖动的问题。

☑️ Self Check before Merge

⚠️ Please check all items below before review. ⚠️

• Doc is updated/provided or not needed
• Demo is updated/provided or not needed
• TypeScript definition is updated/provided or not needed
• Changelog is provided or not needed

[ant-design-bot]

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[afc163]

当@form-item-margin-bottom变量不大于0时隐藏核验信息

需要写解决了什么问题。

[yoyo837]

当@form-item-margin-bottom变量不大于0时隐藏核验信息

需要写解决了什么问题。

改了下看行不行。

[afc163]

可以看看 https://github.com/ant-design/ant-design/wiki/%E8%BD%AE%E5%80%BC%E8%A7%84%E5%88%99%E5%92%8C%E7%89%88%E6%9C%AC%E5%8F%91%E5%B8%83%E6%B5%81%E7%A8%8B#2-%E7%BC%96%E8%BE%91%E6%9B%B4%E6%96%B0%E6%97%A5%E5%BF%97%E4%BB%A5%E5%8F%8A%E5%8D%87%E7%BA%A7%E7%89%88%E6%9C%AC%E5%8F%B7

[afc163]

changelog 可以写：修复 Form 自定义 @form-item-margin-bottom 变量时表单校验抖动的问题。

[afc163]

英文 changelog 补一下。

[codecov]

Codecov Report

Merging #23436 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master   #23436   +/-   ##
=======================================
  Coverage   98.48%   98.48%           
=======================================
  Files         364      364           
  Lines        7315     7315           
  Branches     1957     2004   +47     
=======================================
  Hits         7204     7204           
  Misses        111      111           

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[yoyo837]

英文 changelog 补一下。

Done.