test: fix flaky async-hooks/test-tlswrap

There is a race condition in async-hooks/test-tlswrap. This addresses it
by waiting 5 more ticks if the client has not been destroyed yet.

PR-URL: #15744
Fixes: #14404
Reviewed-By: Refael Ackermann <refack@gmail.com>

test/async-hooks/test-tlswrap.js

@@ -91,6 +91,10 @@ function onsecureConnect() {
     // TODO: why is client not destroyed here even after 5 ticks?
     // or could it be that it isn't actually destroyed until
     // the server is closed?
+    if (client.before.length < 3) {
+      tick(5, tick1);
+      return;
+    }
     checkInvocations(client, { init: 1, before: 3, after: 3 },
                      'client: when client destroyed');
     //