fix: antd.varaible.less mix with default theme

[zombieJ]

[中文版模板 / Chinese template]

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• New feature
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🔗 Related issue link

💡 Background and solution

📝 Changelog

Language	Changelog
🇺🇸 English	Fix antd.variable.less compile mix with default theme variable.
🇨🇳 Chinese	修复 antd.variable.less 编译时会混入默认主题配置的问题。

☑️ 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
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[github-actions]

[codecov]

Codecov Report

Merging #32279 (aa04a34) into master (9d00634) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##            master    #32279   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files          414       414           
  Lines         7571      7571           
  Branches      2125      2125           
=========================================
  Hits          7571      7571           

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[github-actions]

Size Change: -3 B (0%)

Total Size: 917 kB

Filename	Size	Change
./dist/antd.variable.min.css	65.4 kB	-3 B (0%)

ℹ️ View Unchanged

Filename	Size
./dist/antd-with-locales.min.js	353 kB
./dist/antd.compact.min.css	64.8 kB
./dist/antd.dark.min.css	66.1 kB
./dist/antd.min.css	65 kB
./dist/antd.min.js	303 kB

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