minimap viewport border外多了一层outline，导致border样式异常 #5226

Describe the bug

minimap viewport border外多了一层outline，导致border样式异常https://g6.antv.antgroup.com/zh/examples/tool/minimap/#minimap

Your Example Website or App

https://g6.antv.antgroup.com/zh/examples/tool/minimap/#minimap

Steps to Reproduce the Bug or Issue

Expected behavior

希望border可以正常设置样式

Screenshots or Videos

No response

Platform

• OS: [e.g. macOS, Windows, Linux]
• Browser: [e.g. Chrome, Safari, Firefox]
• Version: [e.g. 91.1]

Additional context

No response