tab-container上下滚动会影响到兄弟元素

`tab-container`里，滚动第一个``的内容，当切换到第二个的时候第二个一开始并没有滚动，但是滚动条并不在顶部，显示的是被滚动了的效果
[demo](https://zhao-ping.github.io/Panda-Travel/#/find)

Start with the linked demo and reproduce the issue by scrolling the first , then switching to the second item. Trace the tab-container and tab-container-item behavior to identify where the second item's scroll position is retained; done means each newly selected item begins at the top rather than showing the previous item's scroll state.

Written by the indexing model from the issue text.