fix: use unicode checkmark instead of HTML entity in wxml

miniprogram/pages/register/register.wxml

@@ -22,7 +22,7 @@
     <view class="phone-area">
       <block wx:if="{{phone}}">
         <view class="phone-done">
-          <text class="phone-icon">&#x2713;</text>
+          <text class="phone-icon">✓</text>
           <text class="phone-text">{{phone}}</text>
         </view>
       </block>