fix(接口测试): 修复case无法使用跟随API断言不生效的缺陷

--bug=1013421 --user=王孝刚 [BUG] [接口测试]
github#13861在用例中添加文档结构断言，选择跟随API定义时，不能将API定义中的内容获取过来，导致断言不生效
https://www.tapd.cn/55049933/s/1166871

frontend/src/business/components/api/definition/components/assertion/ApiAssertionsEdit.vue

@@ -64,7 +64,8 @@
           </el-col>
           <el-col class="assertion-remove-btn">
             <el-tooltip :content="$t('test_resource_pool.enable_disable')" placement="top">
-              <el-switch v-model="assertions.enable" class="enable-switch" size="mini" :disabled="assertions.disabled" style="width: 30px;margin-right: 10px"/>
+              <el-switch v-model="assertions.document.enable" class="enable-switch" size="mini"
+                         :disabled="assertions.disabled" style="width: 30px;margin-right: 10px"/>
             </el-tooltip>
             <el-tooltip effect="dark" :content="$t('commons.remove')" placement="top-start">
               <el-button icon="el-icon-delete" type="danger" size="mini" circle @click="remove()"

frontend/src/business/components/api/definition/components/assertion/document/DocumentBody.vue

@@ -222,6 +222,11 @@ export default {
         this.getCase();
       } else if (this.document && this.document.nodeType && this.document.nodeType === "Case" && this.document.apiDefinitionId) {
         this.getAPI(this.document.apiDefinitionId);
+        if (this.document.type === "JSON") {
+          this.document.data.jsonFollowAPI = this.document.apiDefinitionId;
+        } else {
+          this.document.data.xmlFollowAPI = this.document.apiDefinitionId;
+        }
       } else {
         this.getAPI();
       }