Click listener calls chart onClick function

Click listener invokes **two** onclick events:

1. one for data label
2. and the next one for chart `onClick` function.

Does anyone know how to prevent chart onClick event if data-label has been clicked? For now, they are just called both.

I have added `event.stopPropagation()` to data-labels click function but it didn't work

Data Labels plugin config:

```javascript
listeners: {
click: context => {
event.stopPropagation()
var name = context.chart.data.labels[context.dataIndex]
alert(name)
}
}
```

Chart configuration

```javascript
options: {
onClick: click_chart
}
```