fix: Steps style when size="small" and labelPlacement="vertical"

[afc163]

close #21257

🤔 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

close #21257

💡 Background and solution

📝 Changelog

Language	Changelog
🇺🇸 English	Fix Steps text align when size="small" and labelPlacement="vertical".
🇨🇳 Chinese

☑️ Self Check before Merge

• 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 #21258 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master   #21258   +/-   ##
=======================================
  Coverage   97.55%   97.55%           
=======================================
  Files         299      299           
  Lines        6967     6967           
  Branches     1915     1879   -36     
=======================================
  Hits         6797     6797           
  Misses        170      170

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