Pontoon: Update Arabic (ar) localization of AMO
Pontoon: Update Arabic (ar) localization of AMO

Localization authors:
- Abdalrahman Hwoij <howij1995@gmail.com>
- صفا الفليج <safa1996alfulaij@gmail.com>
- mohamedstarwars <mohamedstarwars@gmail.com>

diox/olympia,diox/olympia,mozilla/addons-server,bqbn/addons-server,bqbn/addons-server,eviljeff/olympia,mozilla/addons-server,eviljeff/olympia,diox/olympia,diox/olympia,bqbn/addons-server,mozilla/addons-server,wagnerand/addons-server,mozilla/olympia,mozilla/olympia,bqbn/addons-server,mozilla/olympia,wagnerand/addons-server,wagnerand/addons-server,eviljeff/olympia,eviljeff/olympia,mozilla/addons-server,mozilla/olympia,wagnerand/addons-server