Add cpu-features to server external packages (#51946)

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### What?

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### What?
Adds [cpu-features](https://www.npmjs.com/package/cpu-features) to
external server packages.

### Why?
To prevent developers from having to add ``cpu-features`` to their next
config.

docs/02-app/02-api-reference/05-next-config-js/serverComponentsExternalPackages.mdx

@@ -26,6 +26,7 @@ Next.js includes a [short list of popular packages](https://github.com/vercel/ne
 - `autoprefixer`
 - `aws-crt`
 - `bcrypt`
+- `cpu-features`
 - `cypress`
 - `eslint`
 - `express`

packages/next/src/lib/server-external-packages.json

@@ -13,6 +13,7 @@
   "bcrypt",
   "better-sqlite3",
   "canvas",
+  "cpu-features",
   "cypress",
   "eslint",
   "express",