fix: use correct protocol when -H and --experimental-https are enabled (

#69822)

fixes #69820 

- fixes wrong protocol issue when you run `next dev` with
`--experimental-https` and `-H` option.

To check the PR fixes the issue correctly, run the command below.
```
corepack pnpm next -H 0.0.0.0 --experimental-https YOUR_APP_DIRECTORY
```



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Co-authored-by: JJ Kasper <jj@jjsweb.site>

packages/next/src/server/lib/start-server.ts

@@ -234,7 +234,9 @@ export async function startServer(
 
       port = typeof addr === 'object' ? addr?.port || port : port
 
-      const networkUrl = hostname ? `http://${actualHostname}:${port}` : null
+      const networkUrl = hostname
+        ? `${selfSignedCertificate ? 'https' : 'http'}://${actualHostname}:${port}`
+        : null
       const appUrl = `${
         selfSignedCertificate ? 'https' : 'http'
       }://${formattedHostname}:${port}`