register a timeout in AbortSignal.any test

Refs:  nodejs/node#47821 (comment)

Because of the (i assume) weak references this test doesn't cause the Node.js worker that executes the tests to emit result and therefore completion of the suite.

This change makes it so that a timeout is registered that should never be reached whilst still testing the combinedSignal behaviours.

dom/abort/resources/abort-signal-any-tests.js

@@ -130,12 +130,14 @@ function abortSignalAnyTests(signalInterface, controllerInterface) {
 
     const combinedSignal = signalInterface.any([controller.signal, timeoutSignal]);
 
+    const ref = setTimeout(assert_unreached, 10);
     combinedSignal.onabort = t.step_func_done(() => {
       assert_true(combinedSignal.aborted);
       assert_true(combinedSignal.reason instanceof DOMException,
           "combinedSignal.reason is a DOMException");
       assert_equals(combinedSignal.reason.name, "TimeoutError",
           "combinedSignal.reason is a TimeoutError");
+      clearTimeout(ref);
     });
   }, `${desc} works with signals returned by AbortSignal.timeout() ${suffix}`);