chore: prefer named exports (#8315)

* chore: prefer named exports

* chore: fix import

src/count-down/demo/index.vue

@@ -44,7 +44,7 @@
 import { ref } from 'vue';
 import { useTranslate } from '@demo/use-translate';
 import { ComponentInstance } from '../../utils';
-import Toast from '../../toast';
+import { Toast } from '../../toast';
 
 const i18n = {
   'zh-CN': {

src/count-down/test/index.spec.js

@@ -1,5 +1,5 @@
 import { KeepAlive, nextTick } from 'vue';
-import CountDown from '..';
+import { CountDown } from '..';
 import { mount, later } from '../../../test';
 
 test('should emit finish event when finished', async () => {