🤔 [QUESTION]

### 🐛 Question description [Please make everyone to understand it]

### 💻 Link to minimal reproduction
目前没办法支持一条组数据的时候，配置柱子宽度和间距，期望如下图，有办法配置吗？感谢！

### 🏞 Expected result

### 🚑 Any additional [like screenshots]

* **G2Plot Version**:
* **Platform**:

No file, test, or entry point is identified. The question asks whether bar width and spacing can be configured when displaying one group of data; start by locating the relevant G2Plot bar-chart configuration and compare it with the attached expected result. Done means giving a confirmed configuration path or clearly documenting that the requested behavior is unsupported.

Written by the indexing model from the issue text.