Add automatic testing

[rsanzante]

This boilerplate includes a lot of functionality that can be broken because of new commits. We need to test offered functionalities automatically.

Next steps

Figure out how to test it. We need an environment that runs composer project and has docker and docker compose available.

[rsanzante]

Work is being done in the feature/add-testing-base branch.

shellspec has bee chosen to run tests. It is a BDD unit testing framework for POSIX shells, and this boilerplate can be tested using console commands.

Currently, tests work locally but not in Github. In Github, the problem is the host uses the user id 1001 while the containers use the id 1000.

To run tests locally do:

• Clone the repo
• Run composer install
• Run the asistant (it will be run automatically)
• Download the shelspec library (wget https://github.com/shellspec/shellspec/releases/download/0.28.1/shellspec-dist.tar.gz && tar xfvz shellspec-dist.tar.gz)

Then run the tests running the downloaded shellspec binary in the root folder of the boilerplate.