docs: Update Breadcrumb items type

[rapsealk]

Hi ant-design!

This PR updates the type of Breadcrumb's items property, from items[] to ItemType[].

[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
• Enhancement feature
• Internationalization
• Refactoring
• Code style optimization
• Test Case
• Branch merge
• Workflow
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🔗 Related issue link

💡 Background and solution

📝 Changelog

Language	Changelog
🇺🇸 English	Update the type of Breadcrumb's items on document.
🇨🇳 Chinese	更新文档上面包屑项目的类型。

☑️ Self-Check before Merge

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• 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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Visual Regression Report for PR #46399

Target branch: master (82777bc)

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Congrats! No visual-regression diff found

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (82777bc) 100.00% compared to head (0dbb338) 100.00%.

Additional details and impacted files

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  Coverage   100.00%   100.00%           
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  Files          708       708           
  Lines        12108     12108           
  Branches      3211      3211           
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  Hits         12108     12108           

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