Update and rename cn.lua to zh-cn.lua

Author: ShangYi7

locale/cn.lua locale/zh-cn.lualocale/cn.lua renamed to locale/zh-cn.lua

@@ -120,10 +120,10 @@ local Translations = {
     },
 }
 
-if GetConvar('qb_locale', 'en') == 'cn' then
+if GetConvar('qb_locale', 'en') == 'zh-cn' then
     Lang = Locale:new({
         phrases = Translations,
         warnOnMissing = true,
         fallbackLang = Lang,
     })
-end
+end