[Bug] 热力图色块布局优化

[kkxxkk2019]

Version

latest

Link to Minimal Reproduction

https://visactor.io/vchart/demo/heatmap-chart/basic-heatmap

Steps to Reproduce

1. 热力图图表应该默认自动填充图表宽高
2. 相邻色块之间需要默认相连，现在移除 region 配置布局就有问题

Current Behavior

NA

Expected Behavior

NA

Environment

- OS:
- Browser:
- Framework:

Any additional comments?

No response

[xuefei1313]

问题定位：热力图使用cell图元绘制，在vrender中是symbol，内置图形不支持size中配置不想等的值，导致只能出现正方形。