fix: FormItem with help

[zombieJ]

🤔 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

resolve #23882

close #23883

💡 Background and solution

📝 Changelog

Language	Changelog
🇺🇸 English	Fix Form.Item help style issue when validateStatus is not error.
🇨🇳 Chinese	修复 Form.Item help 在 validateStatus 不是 error 时的样式问题。

☑️ 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]

[zombieJ]

jsdom 没有动画阶段，消失的 className 没法测，蛋疼

[codesandbox-ci]

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Sandbox	Source
antd reproduction template	Configuration
antd reproduction template	Issue #23882

[codecov]

Codecov Report

Merging #23945 into master will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master   #23945   +/-   ##
=======================================
  Coverage   98.77%   98.77%           
=======================================
  Files         364      364           
  Lines        7267     7270    +3     
  Branches     2013     2025   +12     
=======================================
+ Hits         7178     7181    +3     
  Misses         89       89           

Impacted Files	Coverage Δ
components/form/FormItem.tsx	99.15% <100.00%> (+0.02%)	⬆️

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