Remove myget for buildTools (#9081)

Author: Francisco-Gamino

NuGet.config

@@ -5,7 +5,6 @@
     <add key="azure_app_service" value="https://www.myget.org/F/azure-appservice/api/v3/index.json" />
     <add key="azure_app_service_staging" value="https://www.myget.org/F/azure-appservice-staging/api/v2" />
     <add key="azure-appservice-test" value="https://azfunc.pkgs.visualstudio.com/e6a70c92-4128-439f-8012-382fe78d6396/_packaging/azure-appservice-test%40Local/nuget/v3/index.json" />
-    <add key="buildTools" value="https://www.myget.org/F/30de4ee06dd54956a82013fa17a3accb/" />
     <add key="Microsoft.Azure.Functions.PowerShellWorker" value="https://azfunc.pkgs.visualstudio.com/e6a70c92-4128-439f-8012-382fe78d6396/_packaging/Microsoft.Azure.Functions.PowerShellWorker/nuget/v3/index.json" />
     <add key="AzureFunctionsRelease" value="https://azfunc.pkgs.visualstudio.com/e6a70c92-4128-439f-8012-382fe78d6396/_packaging/AzureFunctionsRelease/nuget/v3/index.json" />
     <add key="AzureFunctionsPreRelease" value="https://azfunc.pkgs.visualstudio.com/e6a70c92-4128-439f-8012-382fe78d6396/_packaging/AzureFunctionsPreRelease/nuget/v3/index.json" />