Update zh-CN.json

lang/zh-CN.json

@@ -99,7 +99,7 @@
   "metrics.filter.combined": "总和",
   "metrics.filter.domain-only": "只看域名",
   "metrics.filter.raw": "原始",
-  "metrics.languages": "Languages",
+  "metrics.languages": "语言",
   "metrics.operating-systems": "操作系统",
   "metrics.page-views": "页面浏览量",
   "metrics.pages": "网页",