Work CI-CD

- Remove private Azure feed from nuget.config.

***NO_CI***

NuGet.Config

@@ -2,6 +2,5 @@
 <configuration>
     <packageSources>
         <add key="NuGet" value="https://api.nuget.org/v3/index.json" protocolVersion="3" />
-        <add key="Azure Artifacts nanoFramework dev" value="https://pkgs.dev.azure.com/nanoframework/feed/_packaging/sandbox/nuget/v3/index.json" protocolVersion="3" />
     </packageSources>
 </configuration>