Add the continuous integration pipeline aka CI

### Objective

Currently the project isn't a continuous integration pipeline. Therefore, to improve the workflow at moment of push a pull-request and verify the basic code quality i.e. the test and linter of the code it's essential to add.

### Checklist

- [ ] Research about **code style/linter** for **Java**
- [ ] Research about examples of **jhipster** CI for monolith folder struct i.e when are together the webapp and the API
- [ ] Fix the fails tests in the **spring-boot** and **vue** apps
- [ ] Add the `ci.yml` file to automatize the verify of test and linter in vue and java by example can use: `./mvnw verify` for check the test in the API and `./npmw` test for check the test in the client app
- [ ] If **sonar** tool for code quality it's implemented before of implemented this workflow it would be necessary to **integrate it into the CI**