This moves timer patching from a top-level side effect into the `patchFakeAsyncTest` function. Top-level statements are evaluated before the Node patches run and have a chance to patch them with the Zone versions of these timers, meaning `FakeAsyncTestZoneSpec` was repatching the native versions between tests. The fix here is to grab the patched versions of these timers during the `patchFakeAsyncTest` function where we can be confident Node patches have already run.
PR Close#53443