fix: Cascader text overflow in Firefox

[afc163]

[中文版模板 / Chinese template]

🤔 This is a ...

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

🔗 Related issue link

close #25969

💡 Background and solution

📝 Changelog

Language	Changelog
🇺🇸 English	Fix Cascader text overflow bug in Firefox.
🇨🇳 Chinese	修复 Cascader 在 Firefox 下文本和箭头重叠的问题。

☑️ 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]

[ant-design-bot]

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[codecov]

Codecov Report

Merging #26011 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master   #26011   +/-   ##
=======================================
  Coverage   99.57%   99.57%           
=======================================
  Files         373      373           
  Lines        7314     7314           
  Branches     2035     2035           
=======================================
  Hits         7283     7283           
  Misses         31       31           

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[github-actions]

Size Change: -9 B (0%)

Total Size: 785 kB

Filename	Size	Change
./dist/antd.compact.min.css	64.7 kB	+2 B (0%)
./dist/antd.dark.min.css	66 kB	-6 B (0%)
./dist/antd.min.css	64.8 kB	-5 B (0%)

ℹ️ View Unchanged

Filename	Size	Change
./dist/antd-with-locales.min.js	311 kB	0 B
./dist/antd.min.js	279 kB	0 B

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