[bug report] the SVG generated by cascade will mask the hover event of Li element

[ovarte]

Element UI version

2.15.7

OS/Browsers version

win10 / chrome 96

Vue version

2.6.14

Reproduction Link

https://codepen.io/ovarte/pen/gOxVGvz

Steps to reproduce

将列表滑到底部，倒数第三个，鼠标悬浮到右侧时，不会出现子级。审查元素发现： 生成的svg元素遮住了dom元素

What is Expected?

显示正常

What is actually happening?

异常

[element-bot]

Translation of this issue:

Element UI version

2.15.7

OS/Browsers version

win10 / chrome 96

Vue version

2.6.14

Reproduction Link

https://codepen.io/ovarte/pen/gOxVGvz

Steps to reproduce

Slide the list to the bottom, the penultimate, and when the mouse hovers to the right, no children appear. The review found that the generated SVG element obscured the DOM element

What is Expected?

Normal display

What is actually happening?

abnormal