Add some validation around the set of artifacts we produce

[HaoK]

Followup from some of the installer regressions that we hit as part of the arm64 work.

Might be useful to have a test that verifies the builds produce the expected set of installer/msi/artifacts so if we accidentally drop things, we can catch this during a CI.

cc @wtgodbe

[wtgodbe]

Maybe we could have internal builds publish the asset manifest to an LKG location & compare against that. Could even be centralized in Arcade as part of the validation pipeline? CC @dotnet/dnceng

[epananth]

we already publish all the asset manifest in publishArtifacts.. https://dev.azure.com/dnceng/internal/_build/results?buildId=1663541&view=artifacts&pathAsName=false&type=publishedArtifacts

Can you just download from this and add validation around that?