🐛 [BUG] 折线图缩略轴结合point（size自定义函数）后，会导致图表展示不全

### 🐛 折线图缩略轴结合point（size自定义函数）后，会导致图表展示不全

### 💻 Link to minimal reproduction

Please provide a link by forking these links [g2plot](https://codesandbox.io/s/g2plot-reproduction-template-gyej1) or GitHub repo. What is a minimal reproduction, and why is it required?

### 📷 Step to reproduce
```js
import { Line } from '@antv/g2plot';

fetch('https://gw.alipayobjects.com/os/bmw-prod/1d565782-dde4-4bb6-8946-ea6a38ccf184.json')
.then((res) => res.json())
.then((data) => {
const line = new Line('container', {
data,
padding: 'auto',
xField: 'Date',
yField: 'scales',
xAxis: {
tickCount: 5,
},
slider: {
start: 0.5,
end: 1,
},
point: {
size: () => { return 5 },
shape: 'circle',
},

});

line.render();
});
```

### 🏞 Expected result

### 🚑 Any additional [like screenshots]

* **G2Plot Version**: latest v2
* **Platform**: Windows 10

Start with the Line chart configuration in the reproduction, focusing on the interaction between slider and point.size as a function. Run the provided example with the linked data and compare the rendered chart with the expected full display; done means the chart is no longer cut off when both options are enabled.

Written by the indexing model from the issue text.