fix(useClickAway): callback shouldn't be invoked when a dynamic element inside target is clicked

[liuyib]

[中文版模板 / Chinese template]

🤔 This is a ...

• New feature
• Bug fix
• Site / documentation update
• Demo 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

fix: #2321

💡 Background and solution

📝 Changelog

Language	Changelog
🇺🇸 English	fix(useClickAway): callback shouldn't be invoked when a dynamic element inside target is clicked
🇨🇳 Chinese	fix(useClickAway): 点击目标元素内部的动态元素时，不应该调用回调

☑️ 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

[liuyib]

这个 PR 的变动单测模拟不出来，按照 #2321 (comment) 的 demo，人工是可以复现出问题，并且这个 PR 确实能解决问题，但是单测里复现不了，所以就没补单测