Update migrate-from-newtonsoft.md

[anandmeg]

Incorporate github copilot for VS use case

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[gewarren]

@anandmeg You can batch suggestions into a single commit if you accept them from the "Files changed" tab. That helps to cut down on the no. of email notifications and OPS builds.

[anandmeg]

@anandmeg You can batch suggestions into a single commit if you accept them from the "Files changed" tab. That helps to cut down on the no. of email notifications and OPS builds.

Thanks for the tip, @gewarren. Pardon the multiple emails as this PR is still WIP as I continue to iterate and incorporate feedback. I'll mark it ready for review once its final.

[gewarren]

Thanks for adding this!