fix(next): disable turbopack serverExternalPackages warnings (#9147)

### What?
Disables these annoying warnings when running `pnpm dev --turbo`
<img width="656" alt="image"
src="https://github.com/user-attachments/assets/7d0a2990-b5fd-4f5d-a025-665e8e3a7880">
vercel/next.js#68805

### How?
Patches `console.warn` in `withPayload.js`

Can be disabled with `PAYLOAD_PATCH_TURBOPACK_WARNINGS=false` env
variable

packages/next/src/withPayload.js

@@ -13,6 +13,24 @@ export const withPayload = (nextConfig = {}) => {
     env.NEXT_PUBLIC_ENABLE_ROUTER_CACHE_REFRESH = 'true'
   }
 
+  if (process.env.PAYLOAD_PATCH_TURBOPACK_WARNINGS !== 'false') {
+    const consoleWarn = console.warn
+
+    console.warn = (...args) => {
+      // Force to disable serverExternalPackages warnings: https://github.com/vercel/next.js/issues/68805
+      if (
+        typeof args[1] === 'string' &&
+        args[1].includes(
+          'Packages that should be external need to be installed in the project directory, so they can be resolved from the output files.\nTry to install it into the project directory by running',
+        )
+      ) {
+        return
+      }
+
+      consoleWarn(...args)
+    }
+  }
+
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