tls: prevent multiple connection errors

onConnectEnd(), which is called by TLSSocket, has a guard to
prevent being called multiple times, but it does not prevent the
OpenSSL error handler from being called, leading to multiple
error events. This commit adds that piece of missing logic.

PR-URL: https://github.com/nodejs/node/pull/23636
Fixes: https://github.com/nodejs/node/issues/23631


Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Wyatt Preul <wpreul@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>