The distribution tasks supplies the --no-restore option to dotnet. In a build with multiple target frameworks and multiple target architectures this was causing the exception:
[... path]/dotnet.2.1.105/sdk/2.1.105/Sdks/Microsoft.NET.Sdk/build/Microsoft.PackageDependencyResolution.targets(167,5): error : Assets file '[project path]/obj/project.assets.json' doesn't have a target for '.NETStandard,Version=v2.0/linux-x64'. Ensure that restore has run and that you have included 'netstandard2.0' in the TargetFrameworks for your project. You may also need to include 'linux-x64' in your project's RuntimeIdentifiers.