[FEAT] Publish Docker images in GitHub Registry

[ngosang]

Is your feature request related to a problem? Please describe.
Thank you for publishing the Docker image in DockerHub. That is good enough for me, but DockerHub is changing the rules lately.

• https://docs.docker.com/docker-hub/download-rate-limit/
• https://www.infoworld.com/article/3690890/docker-sunsets-free-team-subscriptions-roiling-open-source-projects.html

They reverted the latest decision but it's desirable to have a mirror just in case.

Describe the solution you'd like
Publish the Docker image in DockerHub and in GitHub Container Registry, both.

• GitHub action example to publish both => https://github.com/ngosang/restic-exporter/blob/main/.github/workflows/release-docker.yml
• GitHub Container Registry example image => https://github.com/ngosang/restic-exporter/pkgs/container/restic-exporter

Describe alternatives you've considered
.

Additional context
.

[CorentinTh]

Docker image are now nightly pushed to docker hub and in github registery under the nightly tag (docker pull ghcr.io/corentinth/it-tools:nightly)