meta: update collaborator email in README

Update email for Ujjwal Sharma to correspond to what is specified in
.mailmap and what is used in more recently authored commits.

Author: Trott

README.md

@@ -414,7 +414,7 @@ For information about the governance of the Node.js project, see
 * [rvagg](https://github.com/rvagg) -
 **Rod Vagg** <rod@vagg.org>
 * [ryzokuken](https://github.com/ryzokuken) -
-**Ujjwal Sharma** <ryzokuken@disroot.org> (he/him)
+**Ujjwal Sharma** <usharma1998@gmail.com> (he/him)
 * [saghul](https://github.com/saghul) -
 **Saúl Ibarra Corretgé** <saghul@gmail.com>
 * [santigimeno](https://github.com/santigimeno) -