Pontoon: Update Chinese (zh-CN) localization of MDN
Pontoon: Update Chinese (zh-CN) localization of MDN

Localization authors:
- xcffl <xcffl@outlook.com>

SphinxKnight/kuma,safwanrahman/kuma,safwanrahman/kuma,jwhitlock/kuma,jwhitlock/kuma,yfdyh000/kuma,safwanrahman/kuma,escattone/kuma,Elchi3/kuma,Elchi3/kuma,yfdyh000/kuma,mozilla/kuma,a2sheppy/kuma,escattone/kuma,yfdyh000/kuma,SphinxKnight/kuma,SphinxKnight/kuma,jwhitlock/kuma,jwhitlock/kuma,safwanrahman/kuma,SphinxKnight/kuma,mozilla/kuma,Elchi3/kuma,a2sheppy/kuma,yfdyh000/kuma,a2sheppy/kuma,a2sheppy/kuma,mozilla/kuma,safwanrahman/kuma,jwhitlock/kuma,yfdyh000/kuma,mozilla/kuma,Elchi3/kuma,safwanrahman/kuma,Elchi3/kuma,SphinxKnight/kuma,a2sheppy/kuma,yfdyh000/kuma,mozilla/kuma,SphinxKnight/kuma,escattone/kuma