Info or exists cmd would be nice for on-demand artifact rebuilds

I have an artifact build early in the pipeline that currently the user has to opt-in via a parameter I could auto-compute the necessity of that build if only I could check for the existence of the artifact without having to commit to downloading it as well. This would be an excellent candidate for an agentless server task. Then I could flip the artifact generation switch programmatically to true even if it was set to false by the default settings.

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* ID: 3ae588e5-6e79-0a3e-56fb-78976019b011
* Version Independent ID: 70e209c8-948c-8baf-3472-e1920c498a2c
* Content: [az artifacts universal](https://docs.microsoft.com/en-us/cli/azure/artifacts/universal?view=azure-cli-latest)
* Content Source: [latest/docs-ref-autogen/artifacts/universal.yml](https://github.com/MicrosoftDocs/azure-docs-cli/blob/master/latest/docs-ref-autogen/artifacts/universal.yml)
* GitHub Login: @rloutlaw
* Microsoft Alias: **routlaw**