test: fix internet/test-inspector-help-page

This gets the test to use its own `https.agent` instead of the default
one.

Signed-off-by: Daeyeon Jeong daeyeon.dev@gmail.com

PR-URL: nodejs/node#44025
Refs: nodejs/node#43522
Refs: https://github.com/nodejs/node/actions/workflows/test-internet.yml
Reviewed-By: Paolo Insogna <paolo@cowtech.it>
Reviewed-By: Juan José Arboleda <soyjuanarbol@gmail.com>

test/internet/test-inspector-help-page.js

@@ -14,7 +14,7 @@ const stderr = child.stderr.toString();
 const helpUrl = stderr.match(/For help, see: (.+)/)[1];
 
 function check(url, cb) {
-  https.get(url, common.mustCall((res) => {
+  https.get(url, { agent: new https.Agent() }, common.mustCall((res) => {
     assert(res.statusCode >= 200 && res.statusCode < 400);
 
     if (res.statusCode >= 300)