CI: GitHub Actions built, test and analyzer

[miquelbeltran]

Please describe your new feature request

It would be good to see the library and example projects compilation, test and lint checks results when submitting and reviewing PRs.

Describe the solution you'd like

GitHub actions should provide everything we need.

It would need an action to setup the Java SDK we need, then several run commands to perform the tasks.

It would also be good to see the library building for different Java SDK versions, for that GH Actions allows to setup a matrix of different versions.

Describe alternatives you've considered

None

Additional context

• [x] Conventional Commits
• [ ] Linting
• [ ] Tests/Verification
• [ ] Builds

[TheRealAgentK]

Yeah, I agree. We should have that.