Add Docker releases when a version tag is pushed

[Dedalo314]

The releases are pushed to ghcr.io and Docker Hub with the version tag. The original Docker push in main is also modified to remove a deprecated variable that is no longer used.

What does this PR do?

Adds workflow to push Docker versions as releases.

Before submitting

• Did you make sure title is self-explanatory and the description concisely explains the PR?
• Did you make sure your PR does only one thing, instead of bundling different changes together?
• Did you list all the breaking changes introduced by this pull request?
• Did you test your PR locally with pytest command?
• Did you run pre-commit hooks with pre-commit run -a command?

Did you have fun?

Make sure you had fun coding 🙃