Fixing footer at the bottom with scroll and resize support

This was posted previously:

Goal is to have a footer that'd match the column widths and scroll. Thoughts on how to achieve this? I figured using `onScroll` and listening for the scroll left position could help, but wont help with column different widths. Thoughts?

首先定位 React 组件中的表格页脚以及滚动和调整大小的处理逻辑。比较滚动和调整大小时页脚与列的宽度，然后定义一个可复现的测试用例，展示页脚始终保持对齐且可用；issue 未指定要运行的文件或测试。

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