style(other): modify the Chinese name of the grayscale mode

Author: Azir-11

src/locales/langs/zh-cn.ts

@@ -64,7 +64,7 @@ const local: App.I18n.Schema = {
       dark: '暗黑模式',
       auto: '跟随系统'
     },
-    grayscale: '灰度模式',
+    grayscale: '灰色模式',
     layoutMode: {
       title: '布局模式',
       vertical: '左侧菜单模式',