🐛 [BUG]可滚动柱状图设置minColumnWidth后没有撑开父容器，造成柱子之间重叠

### 🐛 Bug description [Please make everyone to understand it]
在带滚动条柱状图示例中，当设置 minColumnWidth 大于 34 时，屏幕上展示的柱子不会撑开父容器，造成柱子之间挤压重叠
[代码示例](https://codesandbox.io/s/smoosh-water-didtj?file=/index.ts)

### 🏞 Expected result
期望可以通过设置minColumnWidth，来改变柱子的宽度，撑开父容器的宽度，并且不会造成柱子之间的挤压重叠
### 🚑 Any additional [like screenshots]

* **G2Plot Version**: 2.3.40

Start by reproducing the issue in the linked CodeSandbox with G2Plot 2.3.40, focusing on the scrollable bar chart and minColumnWidth above 34. Trace the chart behavior that determines the parent width and column spacing. Done means the configured column width expands the parent container and the displayed columns no longer overlap.

Written by the indexing model from the issue text.