[Bug] Visual Map display Error

### Version

5.4.0

### Link to Minimal Reproduction

https://github.com/2796673723/echarts-visualmap

### Steps to Reproduce

I want to set different colors inside and outside of a range by using `visualMap.` Examples options are as follows:
```javascript
{
show: false,
pieces: [
{
gte: 0,
lte: limit,
color: '#4A90E2',
},
],
outOfRange: { color: '#FF0000' },
}
```

### Current Behavior

The line at the bottom appears in two colors.

### Expected Behavior

As per the settings I want the bottom line to only show blue.

### Environment

```markdown
- OS:Windows10
- Browser:Chrome 110.0.5481.180
- Framework:Vue@2.7
```

### Any additional comments?

_No response_