(main) Automate release using GH Actions

[abelsromero]

Adds release pipeline to do relases from GitHub Action

Closes #141

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What kind of change does this PR introduce? (check at least one)

• [ ] Bugfix
• [ ] Feature
• [ ] Documentation
• [ ] Refactor
• [x] Build improvement
• [ ] Other (please describe)

What is the goal of this pull request? Automate releases to make the release process much easier, less error prone and avoid local configurations. Note it requires:

• Configure secrets in repo
• s4u/setup-maven-action does not work, so under-the-hood actions are used https://github.com/s4u/setup-maven-action/issues/68
• It's still required to manually login into https://oss.sonatype.org to close and release. I'll create a new GPG key only for CI, but the user used to upload to oss.sonatype is a token linked to my account.

Are there any alternative ways to implement this? There's an alternative plugin https://github.com/sonatype/nexus-maven-plugins/tree/main (docs https://central.sonatype.org/publish/publish-maven/), but there hasn't been release since 2016. Still maybe at some point we can review it it allows to close the staging repo automatically.

Are there any implications of this pull request? Anything a user must know?

Is it related to an existing issue?

- [x] Yes #141 - [ ] No *Finally, please add a corresponding entry to CHANGELOG.adoc*

[abelsromero]

Environment and keys configured :tada: