doc: add @joshgav to collaborators

Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
PR-URL: #8146

Author: joshgav

README.md

@@ -234,6 +234,8 @@ more information about the governance of the Node.js project, see
 **Yuval Brik** <yuval@brik.org.il>
 * [joaocgreis](https://github.com/joaocgreis) -
 **João Reis** <reis@janeasystems.com>
+* [joshgav](https://github.com/joshgav) -
+**Josh Gavant** <josh.gavant@outlook.com>
 * [julianduque](https://github.com/julianduque) -
 **Julian Duque** <julianduquej@gmail.com>
 * [JungMinu](https://github.com/JungMinu) -