refactor(composition api): triggerRef 优化类型

pages/composition-api/reactivity/trigger-ref/trigger-ref.uvue

 <template>
   <view class="page">
-    <text id="state-count" class="uni-common-mb">state.count: {{ state['count'] }}</text>
+    <text id="state-count" class="uni-common-mb">state.count: {{ state.count }}</text>
     <button id="increment-state-count-btn" class="uni-common-mb" @click="incrementStateCount">increment
       state.count</button>
     <button id="trigger-ref-state-btn" @click="triggerRefState">trigger state</button>
@@ -8,9 +8,12 @@
 </template>
 
 <script setup>
+  type State = {
+    count: number
+  }
   const state = shallowRef({
     count: 0
-  })
+  } as State)
 
   const incrementStateCount = () => {
     state.value.count++