[various] Use RadioGroup for groupValue and onChanged

[Phantom-101]

Use RadioGroup to avoid deprecated groupValue and onChanged (flutter/flutter#170915)

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[flutter-dashboard]

It looks like this pull request may not have tests. Please make sure to add tests or get an explicit test exemption before merging.

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[stuartmorgan-g]

Thanks for the contribution! Marking as a draft for now since this will require min SDK updates, and that can't be done in the PR until the next stable has shipped.

[stuartmorgan-g]

It should be possible to update this to be landable now that 3.35 has shipped to stable.