fix: Table small header background color

[zombieJ]

🤔 This is a ...

• New feature
• Bug fix
• Site / document update
• Component style update
• TypeScript definition update
• Refactoring
• Code style optimization
• Test Case
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🔗 Related issue link

fix #21933

💡 Background and solution

📝 Changelog

Language	Changelog
🇺🇸 English	Fix Table size=small header background color not align with other size.
🇨🇳 Chinese	修复 Table size=small 表头颜色和其他尺寸不一致的问题。

☑️ 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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[codecov]

Codecov Report

Merging #21942 into master will decrease coverage by 0.04%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master   #21942      +/-   ##
==========================================
- Coverage   97.96%   97.91%   -0.05%     
==========================================
  Files         305      305              
  Lines        7017     7017              
  Branches     1888     1933      +45     
==========================================
- Hits         6874     6871       -3     
- Misses        143      146       +3

Impacted Files	Coverage Δ
components/carousel/index.tsx	93.47% <0%> (-6.53%)	⬇️

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