doc: prefer to sign commits under nodejs repository

PR-URL: #57311
Reviewed-By: Marco Ippolito <marcoippolito54@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Moshe Atlow <moshe@atlow.co.il>
Reviewed-By: Ulises Gascón <ulisesgascongonzalez@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>

Author: RafaelGSS

doc/contributing/releases.md

@@ -111,6 +111,9 @@ The key you use may be a child/subkey of an existing key.
 Additionally, full GPG key fingerprints for individuals authorized to release
 should be listed in the Node.js GitHub README.md file.
 
+> It is recommended to sign all commits under the Node.js repository.
+> Run: `git config commit.gpgsign true` inside the `node` folder.
+
 ## How to create a release
 
 Notes: