Changelog:
- Feature: 'Migrate MathType plugins suite from TravisCI to Github
Actions'.
Migrate test build machine from TravisCI to Github
- Update CHANGELOG
- Fix lint issues on privacy class.
- Add workflow based on 'moodle-plugin-ci'.
- Remove TravisCI script from the project.
- Update .gitignore with custom paths.
- Update CHANGELOG
- Add full matrix to the tests
- Add Moodle env variables.