Use Environment Files instead of set-output in GitHub workflows

[kate-goldenring]

We are getting depreciating warnings in our workflows (for example: https://github.com/project-akri/akri/actions/runs/4639914706):

The set-output command is deprecated and will be disabled soon. Please upgrade to using Environment Files. For more information see: https://github.blog/changelog/2022-10-11-github-actions-deprecating-save-state-and-set-output-commands/

Support it being removed June 1, 2023. Looks like we do not directly use set-output so I wonder if we are bringing it in through one of the actions we use and simply need to update them. For example, bumping actions/upload-artifact@v2 to actions/upload-artifact@v3 may help

[jbpaux]

The PR related to updating GH actions should solve this too #548

[jbpaux]

You can close this issue, it's been resolved as you can see in the latest runs https://github.com/project-akri/akri/actions/runs/4723946299 🥳

[kate-goldenring]

thanks @jbpaux!