test: deflake test-config-file

Port 9229 may already be used by another process. Use a random
available one.

PR-URL: #58799
Reviewed-By: Marco Ippolito <marcoippolito54@gmail.com>
Reviewed-By: Pietro Marchini <pietro.marchini94@gmail.com>
Reviewed-By: LiviaMedeiros <livia@cirno.name>
Reviewed-By: Edy Silva <edigleyssonsilva@gmail.com>
Reviewed-By: Ethan Arrowood <ethan@arrowood.dev>
Reviewed-By: Stefan Stojanovic <stefan.stojanovic@janeasystems.com>

Author: lpinca

test/parallel/test-config-file.js

@@ -239,6 +239,7 @@ test('--inspect=true should be parsed correctly', { skip: !process.features.insp
     '--no-warnings',
     '--experimental-config-file',
     fixtures.path('rc/inspect-true.json'),
+    '--inspect-port', '0',
     '-p', 'require("node:inspector").url()',
   ]);
   match(result.stderr, /^Debugger listening on (ws:\/\/[^\s]+)/);