New translations en.xaml (Chinese Simplified)

[ci skip]

Author: jjw24

Flow.Launcher/Languages/zh-cn.xaml

@@ -368,6 +368,7 @@
     <system:String x:Key="commonOK">更新</system:String>
     <system:String x:Key="commonYes">是</system:String>
     <system:String x:Key="commonNo">否</system:String>
+    <system:String x:Key="commonBackground">背景</system:String>
 
     <!--  Crash Reporter  -->
     <system:String x:Key="reportWindow_version">版本</system:String>