refactor(my/index): 替换退出登录图标为image组件

将原自定义图标组件更换为本地图片资源，统一图标渲染方式

pages/my/index/index.vue

@@ -45,11 +45,7 @@
       </view>
       <view style="background-color: #ffffff" v-else>
         <view class="quit" @click="handleLogin">
-          <u-icon
-            name="tuichudenglu"
-            custom-prefix="custom-icon"
-            class="icon_left"
-          ></u-icon>
+          <image :src="logoutIcon" mode="" class="icon_left"></image>
           去登录
           <uni-icons type="arrowright" class="icon_right"></uni-icons>
         </view>