Update Readme.md

Add pre-requisition of .NET 6 SDK.

examples/EnableServiceProfilerForContainerAppNet6/Readme.md

@@ -16,6 +16,7 @@ In this article, you'll learn the various ways you can:
 ## Pre-requisites
 
 - [An Application Insights resource](https://docs.microsoft.com/en-us/azure/azure-monitor/app/create-new-resource). Make note of the instrumentation key.
+- [.NET 6 SDK](https://dot.net) for creating projects and local build.
 - [Docker Desktop](https://www.docker.com/products/docker-desktop/) to build docker images.
 
 ### Make an example project