Implement CI/CD

[puntope]

User story

As a developer I want to safely commit and ship new code to this repo in an automated way.

How to reproduce the problem

The repository doesn't have yet any CI/CD setup, neither linters or tests, this makes the code and the repositories using our packages unsafe and tedious to maintain.

Describe the solution you'd like

Implement CI/CD with linters and tests.

Acceptance criteria

• There is a test suit for the different packages in the repo
• There is a linter for PHP
• There is a linter for JS
• There is an automated task that runs all of those on each PR (aka, Github Actions)