Fix/chat backbottom resize

[YyumeiZhang]

中文模板 / Chinese Template

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PR description

Fixes #

Changelog

🇨🇳 Chinese

• Fix: 修复 Chat 组件的返回底部按钮在 Chat 尺寸变化后不需要显示时还可见问题

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🇺🇸 English

• Fix: Fixed the problem that the return to bottom button of the Chat component is still visible when it is not needed to be displayed after the Chat size changes.ba

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semi-design    Run #3327

Run Properties:   Passed #3327  •  b88b0aa3a7 ℹ️: Merge ae9e57d168e5d2043ee883101739fa919a97f8b6 into d0284f2f7d4eed416278c679d161...

Project	semi-design
Branch Review	fix/chat-backbottom-resize
Run status	Passed #3327
Run duration	08m 16s
Commit	b88b0aa3a7 ℹ️: Merge ae9e57d168e5d2043ee883101739fa919a97f8b6 into d0284f2f7d4eed416278c679d161...
Committer	YyumeiZhang
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