doc: add pmarchini to collaborators

Fixes: #55053

Author: pmarchini

.mailmap

@@ -419,6 +419,7 @@ Peter Marshall <p.s.marshall0@gmail.com> <petermarshall@chromium.org>
 Peter Marton <email@martonpeter.com> <peter@risingstack.com>
 Peter Paugh <ppaugh@chariotsolutions.com>
 Phillip Johnsen <johphi@gmail.com> <phillip.johnsen@finn.no>
+Pietro Marchini <pietro.marchini94@gmail.com>
 Prateek Singh <prateeksingh1@hotmail.com> <prateek1@ucla.edu>
 Qingyu Deng <i@ayase-lab.com> <bitdqy@hotmail.com>
 Rachel White <loveless@gmail.com>

README.md

@@ -410,6 +410,8 @@ For information about the governance of the Node.js project, see
   **Filip Skokan** <<panva.ip@gmail.com>> (he/him)
 * [pimterry](https://github.com/pimterry) -
   **Tim Perry** <<pimterry@gmail.com>> (he/him)
+* [pmarchini](https://github.com/pmarchini)
+  **Pietro Marchini** <<pietro.marchini94@gmail.com>> (he/him)
 * [Qard](https://github.com/Qard) -
   **Stephen Belanger** <<admin@stephenbelanger.com>> (he/him)
 * [RafaelGSS](https://github.com/RafaelGSS) -