Migrate to GITHUB_STATE and GITHUB_ENV to address deprecations

[myedibleenso]

save-state and set-output commands have been deprecated. We need to migrate to using Environment files:

• https://github.blog/changelog/2022-10-11-github-actions-deprecating-save-state-and-set-output-commands/#patching-your-actions-and-workflows

• https://github.blog/changelog/2022-10-11-github-actions-deprecating-save-state-and-set-output-commands/

[myedibleenso]

Example writing to and referencing values using the new format: https://docs.github.com/en/actions/using-workflows/workflow-commands-for-github-actions#environment-files