[Bug] jitter not working in Y Axis Config

### Version

6.1.0

### Link to Minimal Reproduction

https://echarts.apache.org/examples/zh/editor.html?c=scatter-simple&code=yy8oyczPU7BVqOZSUKhwrMgstgIzFRRKKgtSrRTUkxNLUtPziyrVdcCiKYkliVYK0eqJ6rFAfi1IsJJ4XRUV6rEQkazMkpLUIisFYwMDmDnFqUWZqUCDosEKIMYBRStzk_JzgjOrgMYaGUA0ww2E8kAA5CQdkAU6hlAr0MWNRsUHiTicAU0txcDkAkwN6mDRWiAZy1VrDQA&enc=deflate

### Steps to Reproduce

```js
option = {
xAxis: {
type: 'category',
data: ['a'],
jitter: 300
},
yAxis: {
type: 'category',
data: ['xx'],
jitter: 300
},
series: [
{
symbolSize: 20,
data: [
['a','xx',1],
['a','xx',2],
['a','xx',2],
['a','xx',2],
['a','xx',2],
['a','xx',2],
['a','xx',2],
['a','xx',2],
['a','xx',2],
['a','xx',2],
['a','xx',2],
['a','xx',2],
['a','xx',2],
['a','xx',2],
['a','xx',2],
['a','xx',2],
['a','xx',2],
['a','xx',2],
],
type: 'scatter'
}
]
};

```

### Current Behavior

散点y轴没随机偏移

### Expected Behavior

散点y轴随机偏移

### Environment

```markdown
- OS:
- Browser:
- Framework:
```

### Any additional comments?

_No response_

Start with the linked minimal reproduction and trace how jitter is applied to category axes in the scatter chart. Compare the x-axis and y-axis behavior for the supplied configuration. Done means repeated points receive random y-axis offsets while preserving the expected scatter layout.

Written by the indexing model from the issue text.