doc: update release-stewards with last sec-release

PR-URL: nodejs#50179
Refs: https://github.com/nodejs-private/node-private/issues/485
Reviewed-By: Richard Lau <rlau@redhat.com>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Michael Dawson <midawson@redhat.com>

doc/contributing/security-release-process.md

@@ -30,6 +30,7 @@ The current security stewards are documented in the main Node.js
 | RH and IBM   | Michael         | 2023-Feb-16  |
 | NearForm     | Rafael          | 2023-Jun-20  |
 | NearForm     | Rafael          | 2023-Aug-09  |
+| NearForm     | Rafael          | 2023-Oct-13  |
 | Datadog      | Bryan           |              |
 | IBM          | Joe             |              |
 | Platformatic | Matteo          |              |