fix: 使用 mock 数据 (#2606)

Co-authored-by: liufu.lf <[email protected]>

Author: lxfu1

examples/more-plots/word-cloud/demo/basic.ts

@@ -1,6 +1,6 @@
 import { WordCloud } from '@antv/g2plot';
 
-fetch('https://gw.alipayobjects.com/os/antvdemo/assets/data/world-population.json')
+fetch('https://gw.alipayobjects.com/os/antfincdn/jPKbal7r9r/mock.json')
   .then((res) => res.json())
   .then((data) => {
     const wordCloud = new WordCloud('container', {