🐛 [BUG] legend 的显示的数据条数不正确

https://g2plot.antv.antgroup.com/zh/examples/pie/donut/#statistics
在 该示例中，将某一数据的type文本加长
const data = [
{ type: '分类分类分类分类', value: 27 },
{ type: '分类二', value: 25 },
{ type: '分类三', value: 18 },
{ type: '分类四', value: 15 },
{ type: '分类五', value: 10 },
{ type: '其他', value: 5 },
];

然后添加这个属性让其显示在顶部
legend:{
position:"top"
},

拖动浏览器窗口大小，观察legend 表现，当宽度小到一定的值的时候，data 长度为本来为6，但是页面会显示为7，并且第一条数据渲染不出来。

Start with the donut statistics example at the linked G2Plot URL and reproduce the issue using the provided data and top-positioned legend. Resize the browser until the legend shows seven entries and the first entry is missing; done means the six data items remain correctly represented at narrow widths.

Written by the indexing model from the issue text.