updated readme

Author: Sridhar S

README.md

@@ -15,7 +15,7 @@ This section guides you to use the Syncfusion ASP.NET Core Razor Components UI C
 
 The samples requires the below requirements to run.
 
-* [Visual Studio 2017](https://visualstudio.microsoft.com/downloads/)
+* [Visual Studio 2019](https://visualstudio.microsoft.com/downloads/#2019rc)
 * [.NET Core SDK 3.0 Preview](https://dotnet.microsoft.com/download/dotnet-core/3.0)
 
 ## Documentation