fix: 通知方式的返回null导致页面报错

src/pages/Iot/sys/noticeway.vue

@@ -111,8 +111,8 @@ const getLogo = async () => {
   state.loading = true
   const { data } = await SysController.sysConf()
   state.loading = false
-  state.sys = data
-  resetFields(data.mailConf)
+  state.sys = data || { mailConf: {} }
+  resetFields(data || { mailConf: {} })
 }
 
 onMounted(() => {