feat: auto generate demo test

[xiaosansiji]

🤔 这个 PR 的性质是？

• 日常 bug 修复
• 新特性提交
• 文档改进
• 演示代码改进
• 组件样式/交互改进
• CI/CD 改进
• 重构
• 代码风格优化
• 测试用例
• 分支合并
• 其他

🔗 相关 Issue

💡 需求背景和解决方案

关联 common pr: Tencent/tdesign-common#387
在 common 中统一维护自动生成 demo snapshot test 的脚本；
npm run test 内每次自动生成缺的 test 文件，防止忘记手动执行 npm run test:demo 补充

📝 更新日志

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⚠️ 请自检并全部勾选全部选项。⚠️

• 文档已补充或无须补充
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[github-actions]

Size Change: 0 B

Total Size: 650 kB

ℹ️ View Unchanged

Filename	Size
./dist/tdesign.css	42.4 kB
./dist/tdesign.js	363 kB
./dist/tdesign.min.css	37.6 kB
./dist/tdesign.min.js	207 kB

[github-actions]

[github-actions]

Size Change: 0 B

Total Size: 650 kB

ℹ️ View Unchanged

Filename	Size
./dist/tdesign.css	42.4 kB
./dist/tdesign.js	363 kB
./dist/tdesign.min.css	37.6 kB
./dist/tdesign.min.js	207 kB

[codecov-commenter]

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@@            Coverage Diff             @@
##             develop     #579   +/-   ##
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  Coverage           ?   64.38%           
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  Files              ?      389           
  Lines              ?    13629           
  Branches           ?     2532           
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  Hits               ?     8775           
  Misses             ?     4606           
  Partials           ?      248           

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