Release management: improve semantic versioning

[damyan]

Present tag $MAJOR_VERSION (in this case: v1) pointing to the last released version. In that case all action consumers can stick to the v1 version, without needing to keep track of version changes with dependabot and updating their caller actions each time.

See also https://docs.github.com/en/actions/creating-actions/about-custom-actions#using-tags-for-release-management for details.

[damyan]

v1/v2/v3 still missing. It is just about proper tagging, isn't it?

[damyan]

Can you, kindly, at least comment on that one? We also have a duplicate issue, #61