fix: input示例 placeholder-class设置placeholder字体大小

pages/component/input/input.uvue

@@ -48,7 +48,7 @@
           <input id="uni-input-placeholder1" class="uni-input" :placeholder-style="inputPlaceHolderStyle" placeholder="占位符文字颜色为红色" />
         </view>
         <view class="input-wrapper">
-          <input id="uni-input-placeholder2" class="uni-input" :placeholder-class="inputPlaceHolderClass" placeholder="占位符背景色为绿色" />
+          <input id="uni-input-placeholder2" class="uni-input" :placeholder-class="inputPlaceHolderClass" placeholder="占位符字体大小为10px" />
         </view>
       </view>
 
@@ -336,9 +336,6 @@
   }
 
   .uni-input-placeholder-class {
-    background-color: green;
-  }
-  .uni-input-placeholder-class-ts {
-    background-color: orange;
+    font-size: 10px;
   }
 </style>