use feed with signed wix package

[tgauth]

PR Summary

• update nuget feed to use signed WiX artifact

PR Checklist

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• Summarized changes
• Make sure all .h, .cpp, .cs, .ps1 and .psm1 files have the correct copyright header
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• Testing - New and feature
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• Tooling
  • I have considered the user experience from a tooling perspective and don't believe tooling will be impacted.
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