This repository contains a sample Drupal 8 project with Continuous Integration via Travis CI. When a pull request is created against this repository, Travis CI will add the following status messages:
For you to see the details of each individual job, you will have to click on Details at the above screenshot, which will show a page similar like the following one:
If you want to install this into your project, follow instructions at the CircleCI installer for Drupal 8.