ci: Enforce unit tests on every pull request

[brenoepics]

Related to #783

Adds a new GitHub Actions workflow to enforce unit tests on every pull request to the main branch.

• Workflow Configuration: Introduces testing.yml in the .github/workflows directory, activating on pull requests targeting the main branch.
• Testing Environment Setup: Configures the workflow to run on the latest Ubuntu version, sets up JDK 17, and executes ./gradlew test to run unit tests.
• Automatic Test Enforcement: Ensures that pull requests cannot be merged unless all unit tests pass, enhancing code quality and preventing regressions. (To block the merge when the action fails, the repository owner must set a rule in the repository settings)

[brenoepics]

@Ashinch : Each pull request should include sufficient unit tests covering new and modified code.

This would be a little more complicated, I can't do it in an action without some external action/plugin, I think it's better to discuss this, have you considered SonarCloud, CodeCov or Qodana...? They have free options for open source projects.

example from another repository of mine:

Or just checking that the tests didn't fail is ok?

[Ashinch]

Hi, @brenoepics

Thank you for your work on this! For now, we just need to ensure that the unit tests are executed. I am currently working on increasing the test coverage of our infrastructure. “Sufficient unit tests covering” is more of an expectation rather than a mandatory requirement at the moment.