feat: Avatar.Group add size props

[hengkx]

[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
• Other (about what?)

🔗 Related issue link

#27068 #27138

💡 Background and solution

📝 Changelog

Language	Changelog
🇺🇸 English	Avatar.Group add size props.
🇨🇳 Chinese	Avatar.Group 增加 size 属性。

☑️ 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

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View rendered components/avatar/demo/group.md
View rendered components/avatar/index.en-US.md
View rendered components/avatar/index.zh-CN.md

[ant-design-bot]

[ant-design-bot]

[codesandbox-ci]

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[codecov]

Codecov Report

Merging #27348 into feature will not change coverage.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##           feature    #27348   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files          389       389           
  Lines         7399      7399           
  Branches      2082      2082           
=========================================
  Hits          7399      7399           

Impacted Files	Coverage Δ
components/avatar/avatar.tsx	100.00% <ø> (ø)
components/avatar/group.tsx	100.00% <100.00%> (ø)

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[github-actions]

Size Change: +25 B (0%)

Total Size: 792 kB

Filename	Size	Change
./dist/antd-with-locales.min.js	314 kB	+11 B (0%)
./dist/antd.min.js	278 kB	+14 B (0%)

ℹ️ View Unchanged

Filename	Size	Change
./dist/antd.compact.min.css	66.4 kB	0 B
./dist/antd.dark.min.css	67.7 kB	0 B
./dist/antd.min.css	66.4 kB	0 B

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