use different tab name

Author: linglingye001

articles/azure-app-configuration/howto-geo-replication.md

@@ -179,7 +179,7 @@ You can specify one or more endpoints of a geo-replication-enabled App Configura
 
 The automatically discovered replicas will be selected and used randomly. If you have a preference for specific replicas, you can explicitly specify their endpoints. This feature is enabled by default, but you can refer to the following sample code to disable it.
 
-### [.NET](#tab/dotnet)
+### [.NET](#tab/Dotnet)
 
 Edit the call to the `AddAzureAppConfiguration` method, which is often found in the `program.cs` file of your application.