Fix grammatical error in docs (#53197)

Changed 'created' to 'create' for improved grammar and clarity in the documentation.

Find it under `Custom App`
[https://nextjs.org/docs/pages/building-your-application/routing/custom-app](url)

docs/03-pages/01-building-your-application/01-routing/04-custom-app.mdx

@@ -5,7 +5,7 @@ description: Control page initialization and add a layout that persists for all
 
 Next.js uses the `App` component to initialize pages. You can override it and control the page initialization and:
 
-- Created a shared layout between page changes
+- Create a shared layout between page changes
 - Inject additional data into pages
 - [Add global CSS](/docs/pages/building-your-application/styling)