Removed Blazor extension info

The Blazor VS extension is no longer need with Preview 7+

_contentTemplates/common/get-started.md

@@ -23,8 +23,6 @@
 
 
 #after-you-run-vanilla
-You need to install the [Blazor VS Extensions](https://marketplace.visualstudio.com/items?itemName=aspnet.blazor) in order to get the necessary app templates.
-
 >tip Make sure that you have [.NET Core 3.0](https://dotnet.microsoft.com/download/dotnet-core/3.0) and [Visual Studio 2019 **Preview**](https://visualstudio.microsoft.com/vs/preview/) installed. You must use the Preview version of Visual Studio for working with Blazor apps.
 >
 > The latest version of Telerik UI for Blazor is `{{site.uiForBlazorLatestVersion}}` and it supports .NET Core 3 `Preview 7`.