Update Next.js <> Tailwind guide. (#781)

Author: leerob

src/pages/docs/guides/nextjs.mdx

@@ -8,9 +8,11 @@ tool: Next.js
 reference:
   name: Create Next App
   link: https://nextjs.org/docs/api-reference/create-next-app
-script: npx create-next-app
+script: npx create-next-app -e with-tailwindcss
 ```
 
+This will automatically configure your Tailwind setup based on the official Next.js example. If you'd like to configure Tailwind manually, continue with the rest of this guide.
+
 ---
 
 ```preval setup