doc fix layout breakpoints url

[chenshuai2144]

🤔 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

💡 Background and solution

因为锚点的大小写问题，导致不能跳转到正确的位置

📝 Changelog

Language	Changelog
🇺🇸 English	no
🇨🇳 Chinese	no

☑️ 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

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View rendered components/layout/index.en-US.md
View rendered components/layout/index.zh-CN.md

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[codecov]

Codecov Report

Merging #19537 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master   #19537   +/-   ##
=======================================
  Coverage   97.78%   97.78%           
=======================================
  Files         282      282           
  Lines        7640     7640           
  Branches     2158     2155    -3     
=======================================
  Hits         7471     7471           
  Misses        169      169

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