fix(WingBlank): 修复预览报错问题

Author: nullptr-z

packages/core/src/WingBlank/README.md

@@ -8,7 +8,7 @@ WingBlank 两翼留白
 
 ```jsx mdx:preview&background=#bebebe29
 import React,{Component} from 'react';
-import { Text } from 'react-native';
+import { Text, View } from 'react-native';
 import { WingBlank } from '@uiw/react-native';
 
 function Demo() {
@@ -50,7 +50,7 @@ export default Demo
 
 两翼留白不换行
 
-```jsx  mdx:preview
+```jsx mdx:preview&background=#bebebe29
 import React,{Component,Fragment} from 'react';
 import { Text } from 'react-native';
 import { WingBlank } from '@uiw/react-native';