[Bug] Sankey `emphasis.lineStyle.color: 'target'` not work

[xieyhn]

Version

5.4.2

Link to Minimal Reproduction

https://echarts.apache.org/examples/zh/editor.html?c=sankey-simple&code=PYBwLglsB2AEC8sDeAoWsDOBTAThLGAXMmurGAJ4hbEDkGAhtANZYW0A0p6AJg2A2IBtbmVRkJsaAwC2NWLQa1R6AL5dJJTemly6AI04qyEMFhkBlSgBt547egDGwa8Bx0cWHsoerjfiQBdDTJrCBYiWBFNe00MYABXHEd5RSMHARwAcywwA3TtADcGawT5AFYQzTDoLCsKW2JY7WdXdwV4pJSfbXVjdHMQAAsGDAhI5urwups7fslWtzpMnLAe33mAyT6g0j9VAG4gA

Steps to Reproduce

1. Hover the line between a and b

Current Behavior

The color of the line between a and b is gray.

Expected Behavior

The color of the line between a and b is red(the color of b).

Environment

- OS: MacOS 13.3
- Browser: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36
- Framework: -

Any additional comments?

No response