Wrong nuget.config generated for private feeds

[mbp]

Using on-premise Windows or Linux agent with latest .NET Core SDK 2.1.500 installed, it is not possible to restore packages with "dotnet restore" using the DotNetCoreCli task. You get 401 Unauthorized

It seems the temporary nuget.config file generated is wrong.

<configuration>
  <packageSources>
    <add key="NuGetOrg" value="https://api.nuget.org/v3/index.json"/>
    <add key="24175d4e-5754-49d7-8f7e-11a212b7dae1" value="https://MYORG.pkgs.visualstudio.com/_packaging/24175d4e-5754-49d7-8f7e-11a212b7dae1/nuget/v3/index.json"/>
  </packageSources>
  <packageSourceCredentials>
    <_x0032_4175d4e-5754-49d7-8f7e-11a212b7dae1>
      <add key="Username" value="VssSessionToken"/>
      <add key="ClearTextPassword" value="SECRET"/>
    </_x0032_4175d4e-5754-49d7-8f7e-11a212b7dae1>
  </packageSourceCredentials>
</configuration>

The <_x0032_4175d4e-5754-49d7-8f7e-11a212b7dae1> is wrong, it should be <24175d4e-5754-49d7-8f7e-11a212b7dae1>

Related issue/comment: NuGet/Home#7516 (comment)

[nkolev92]

My comment wasn't clear enough.
The bug is on NuGet side.
See tracking here:
NuGet/Home#7517