test: fix failing test suite (#1166)

src/client/app/index.ts

@@ -16,7 +16,7 @@ import { dataSymbol, initData } from './data'
 import { Content } from './components/Content'
 import { ClientOnly } from './components/ClientOnly'
 
-export const NotFound = Theme.NotFound || (() => '404 Not Found')
+const NotFound = Theme.NotFound || (() => '404 Not Found')
 
 const VitePressApp = {
   name: 'VitePressApp',

src/client/theme-default/components/VPContent.vue

@@ -2,7 +2,7 @@
 import { useRoute, useData } from 'vitepress'
 import { useCopyCode } from '../composables/copy-code'
 import { useSidebar } from '../composables/sidebar'
-import { NotFound } from '../../app'
+import Theme from '/@theme/index'
 import VPPage from './VPPage.vue'
 import VPHome from './VPHome.vue'
 import VPDoc from './VPDoc.vue'
@@ -11,6 +11,8 @@ const route = useRoute()
 const { frontmatter } = useData()
 const { hasSidebar } = useSidebar()
 
+const NotFound = Theme.NotFound || (() => '404 Not Found')
+
 useCopyCode()
 </script>