伸缩列不起作用

[Booom007]

The issue which is not created via https://vuecomponent.github.io/issue-helper/ will be closed immediately.
### Verson
1.4.10

使用原例，在鼠标放在表头边时，没有像例子一样出现伸缩图标，

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[github-actions]

This issue has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.