Update workflows for Katie's departure

[krivard]

Prerequisites:

• [x] Unless it is a hotfix it should be merged against the dev branch
• [x] Branch is up-to-date with the branch to be merged with, i.e. dev
• [x] Build is successful
• [x] Code is cleaned up and formatted

Summary

Convert review assignments to assignees and switch from Katie to george. Review assignments are handled through the release-runner rotation.

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