Use GoReleaser to handle Docker image releasing

[LeoColomb]

This would help to build the Docker image and push it automatically to a registry.
The chosen registry is GitHub Container Registry, to keep it close to the repository and in the way to facilitate its use with Kubernetes templates/Helm charts.

[Kooper]

I didn't work with ghcr before, will take a look at the authentication and configuration tomorrow. Thank you!

[LeoColomb]

@Kooper No worries 😊
Nothing to configure or authenticate, all is completely transparent with GitHub Actions.
But of course don't hesitate to check out their docs 😊 https://docs.github.com/en/packages/working-with-a-github-packages-registry/working-with-the-container-registry