Add Dockerfile with minimal supported Python version (3.10)

[tchemineau]

Description

The idea is to provide a minimal Dockerfile to build a container image that can run stacks tool properly.

I would like to reuse that mechanism to eventually publish the container image to docker hub, and use it in the CI to do some more advanced testing.

For my use-case, I found out the result container image very useful to quickly run stacks encrypt command line.

Let me know your thought, and if that could be useful.

Type of Change

• [ ] Bug Fix
• [x] New Feature
• [ ] Breaking Change
• [ ] Refactor
• [ ] Documentation
• [ ] Other (please describe)

Checklist

• [ ] I have read the contributing guidelines
• [ ] Existing issues have been referenced (where applicable)
• [ ] I have verified this change is not present in other open pull requests
• [ ] Functionality is documented
• [ ] All code style checks pass
• [ ] New code contribution is covered by automated tests
• [ ] All new and existing tests pass

[ribejara-te]

This is an interesting addition to the repo, however:

• We don't currently have plans to support the pipeline and registry to build it automatically, so users may build the image themselves if they want to use it.
• The current Dockerfile as it stands has several number of flaws, I'll put those in inline code review comments.

Otherwise, we're open to accepting this, thanks for your contribution!