chore: prefer named exports (#8315)

* chore: prefer named exports

* chore: fix import

src/sidebar/demo/index.vue

@@ -41,7 +41,7 @@
 <script lang="ts">
 import { reactive, toRefs } from 'vue';
 import { useTranslate } from '@demo/use-translate';
-import Toast from '../../toast';
+import { Toast } from '../../toast';
 
 const i18n = {
   'zh-CN': {

src/sidebar/test/index.spec.tsx

@@ -1,7 +1,7 @@
 import { ref } from 'vue';
 import { mount } from '../../../test';
-import Sidebar from '..';
-import SidebarItem from '../../sidebar-item';
+import { Sidebar } from '..';
+import { SidebarItem } from '../../sidebar-item';
 
 test('should emit change event when active item changed', () => {
   const onChange = jest.fn();