Github action "Push Docker Image"doesn't work with Uppercase repository name

[Lp-Francois]

Hello!

During the Argo Image Updater exercise, it requires to use docker push step, but it fails with uppercase repository name (like mine 😅)

Seems to be related to this issue: docker/build-push-action#37

How about using another "unique identifier" than the repository name? Or lowercase the name? (https://github.com/orgs/community/discussions/25768)

Best,

[Lp-Francois]

After giving a try to the GitHub action: ASzc/change-string-case-action@v2, the workflow worked ✅

Example commit: Lp-Francois@1121fb3
Example workflow: https://github.com/Lp-Francois/gitops-cert-level-2-examples/actions/runs/3503615687

Let me know if I should push a PR

[todaywasawesome]

@Lp-Francois I think that would make a great PR. I don't know if there are any other possible values in a repo name that would be invalid for an image, it would be nice to cover those but I'd settle for having this PR today :)

[kostis-codefresh]

Fixed as part of #66

Thanks!