Fix official build WIF package publishing

[JoeRobich]

The official build fails during pipeline validation because 1ES.PublishNuget@1 requires an ExternalNuGetFeed service connection, but dnceng-devdiv-vs-feed-push is a WIF-backed workloadidentityuser connection.

This ports the fix from dotnet/roslyn#84490:

• authenticate to the DevDiv VS feed with NuGetAuthenticate@1
• publish the shipping packages with dotnet nuget push using the credential provider
• preserve package-conflict behavior with --skip-duplicate

Failed build: https://dev.azure.com/dnceng/internal/_build/results?buildId=3055126&view=results
Upstream fix: dotnet/roslyn@e7680f2

Test Build: https://dev.azure.com/dnceng/internal/_build/results?buildId=3065575&view=results

[missymessa]

LGTM

Also, the pipeline should be pre-authorized to use whatever service connections it needs here, but let me know if you have any issues after this merges.

[JoeRobich]

Also, the pipeline should be pre-authorized to use whatever service connections it needs here, but let me know if you have any issues after this merges.

It did need an approval but Haruna got us straightened out. Thanks!

[missymessa]

Also, the pipeline should be pre-authorized to use whatever service connections it needs here, but let me know if you have any issues after this merges.

It did need an approval but Haruna got us straightened out. Thanks!

Of course he did, he's super fast :)