doc: add italoacasas to collaborators

PR-URL: #9677
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

Author: Italo A. Casas

README.md

@@ -239,6 +239,8 @@ more information about the governance of the Node.js project, see
 **Ilkka Myller** <ilkka.myller@nodefield.com>
 * [isaacs](https://github.com/isaacs) -
 **Isaac Z. Schlueter** <i@izs.me>
+* [italoacasas](https://github.com/italoacasas)
+**Italo A. Casas**  <me@italoacasas.com>
 * [iWuzHere](https://github.com/iWuzHere) -
 **Imran Iqbal** <imran@imraniqbal.org>
 * [JacksonTian](https://github.com/JacksonTian) -