doc: fix a broken collaborator github link

PR-URL: #1204
Reviewed-By: Jeremiah Senkpiel <fishrock123@rocketmail.com>

Author: Aleksanteri Negru-Vode

README.md

@@ -285,7 +285,7 @@ information about the governance of the io.js project, see
 * **Julian Duque** ([@julianduque](https://github.com/julianduque)) <julianduquej@gmail.com>
 * **Johan Bergström** ([@jbergstroem](https://github.com/jbergstroem)) <bugs@bergstroem.nu>
 * **Roman Reiss** ([@silverwind](https://github.com/silverwind)) <me@silverwind.io>
-* **Petka Antonov** ([@petkaantonov](https://github.com/petkaanotnov)) <petka_antonov@hotmail.com>
+* **Petka Antonov** ([@petkaantonov](https://github.com/petkaantonov)) <petka_antonov@hotmail.com>
 * **Yosuke Furukawa** ([@yosuke-furukawa](https://github.com/yosuke-furukawa)) <yosuke.furukawa@gmail.com>
 
 Collaborators follow the [COLLABORATOR_GUIDE.md](./COLLABORATOR_GUIDE.md) in