update

Author: vicancy

build/sources.props

@@ -4,7 +4,6 @@
   <PropertyGroup Label="RestoreSources">
     <RestoreSources>
       $(DotNetRestoreSources);
-      https://dotnetfeed.blob.core.windows.net/dotnet-core/index.json;
       https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet-tools/nuget/v3/index.json;
     </RestoreSources>
     <RestoreSources Condition="'$(DotNetBuildOffline)' != 'true'">