Tag validation

[Boomatang]

What

Add a validation step to the make prepare-release that checks if the version that is being build for already has a tag created in github.

Why

At no point should release be prepared for existing releases, and sense this is something that we can check, we should.

How

The Github API should be used for checking that the tags exists. This would remove need, and possible error point of the local repo not having its tags up to date.

Sample command can look like.

http https://api.github.com/repos/kuadrant/kuadrant-operator/tags | jq 'any(.[]; .name == "v1.0.2-rc1")' 

Done

The checking of tags is added to the pre-validation steps of the prepare-release target.