chore: use preventDefault util (#4412)

src/button/README.zh-CN.md

@@ -29,7 +29,7 @@ Vue.use(Button);
 
 ```html
 <van-button plain type="primary">朴素按钮</van-button>
-<van-button plain type="danger">朴素按钮</van-button>
+<van-button plain type="info">朴素按钮</van-button>
 ```
 
 ### 细边框
@@ -38,7 +38,7 @@ Vue.use(Button);
 
 ```html
 <van-button plain hairline type="primary">细边框按钮</van-button>
-<van-button plain hairline type="danger">细边框按钮</van-button>
+<van-button plain hairline type="info">细边框按钮</van-button>
 ```
 
 ### 禁用状态
@@ -47,7 +47,7 @@ Vue.use(Button);
 
 ```html
 <van-button disabled type="primary">禁用状态</van-button>
-<van-button disabled type="danger">禁用状态</van-button>
+<van-button disabled type="info">禁用状态</van-button>
 ```
 
 ### 加载状态
@@ -57,7 +57,7 @@ Vue.use(Button);
 ```html 
 <van-button loading type="primary" />
 <van-button loading type="primary" loading-type="spinner" />
-<van-button loading type="danger" loading-text="加载中..." />
+<van-button loading type="info" loading-text="加载中..." />
 ```
 
 ### 按钮形状
@@ -66,7 +66,7 @@ Vue.use(Button);
 
 ```html 
 <van-button square type="primary">方形按钮</van-button>
-<van-button round type="danger">圆形按钮</van-button>
+<van-button round type="info">圆形按钮</van-button>
 ```
 
 ### 图标按钮
@@ -76,7 +76,7 @@ Vue.use(Button);
 ```html 
 <van-button icon="star-o" type="primary" />
 <van-button icon="star-o" type="primary">按钮</van-button>
-<van-button icon="https://img.yzcdn.cn/vant/logo.png" type="danger">按钮</van-button>
+<van-button icon="https://img.yzcdn.cn/vant/logo.png" type="info">按钮</van-button>
 ```
 
 ### 按钮尺寸