Web-platform test webtransport constructor uses invalid URLs

Differential Revision: https://phabricator.services.mozilla.com/D170030

bugzilla-url: https://bugzilla.mozilla.org/show_bug.cgi?id=1817130
gecko-commit: dab6b577190ab82affbdbcf674a4c9939191fea7
gecko-reviewers: edgul

webtransport/constructor.https.any.js

@@ -1,6 +1,7 @@
 // META: global=window,worker
 // META: script=/common/get-host-info.sub.js
 // META: script=resources/webtransport-test-helpers.sub.js
+// META: script=/common/utils.js
 
 const BAD_URLS = [
   null,
@@ -33,7 +34,8 @@ const OPTIONS = [
 
 for (const options of OPTIONS) {
   promise_test(async t => {
-    const wt = new WebTransport(`https://${HOST}:0/`, options );
+    const id = token();
+    const wt = new WebTransport(webtransport_url(`client-close.py?token=${id}`), options );
     await wt.ready;
     wt.close();
   }, "WebTransport constructor should allow options " + JSON.stringify(options));