Improve Docker tag selection

[Supereg]

Problem

Currently, we always pull the latest docker image for SwiftLint. This might cause unwanted breaking changes, as the Docker image is based on the latest changes in the main branch.
We choose this way originally to not have an action that you always have to manually upgrade, even for minor versions, but that automatically updates to the latest release of SwiftLint. This becomes a problem though with the latest tag if the "latest version" isn't even available and you fail to locally reproduce the issue.

Solution

Use a tagged image as available on GitHub: https://github.com/realm/SwiftLint/pkgs/container/swiftlint.
Ideally, we can automatically determine the latest tag. At the same time we could aim for customizability to set a certain major or minor version limit or even force a specific SwiftLint version.

Additional context

SwiftLint is using semantic versioning. They also publish prerelease version tagged like 0.51.0-rc.2. It would make sense to employ a library like semver to allow for flawless computation of version labels.

Code of Conduct

• I agree to follow this project's Code of Conduct and Contributing Guidelines

[PSchmiedmayer]

As the docker builds are currently failing, as reported by @vishnuravi:

I think that the actual solution would be fixing this in the SwiftLint repo: https://github.com/realm/SwiftLint/blob/main/.github/workflows/docker.yml. The latest tag should be only applied if it is an actual release, and if not, it should just use, e.g., a main tag or something like that.

You can pass multiple tags into the GitHub action that pushed the image as documented here: https://docs.docker.com/build/ci/github-actions/manage-tags-labels/.