Debian 8 CI test failing with 'No package matching 'php7.1-yaml'

[geerlingguy]

Issue Type

• Bug Report

Full console output

TASK [geerlingguy.php : Ensure PHP packages are installed.] ********************
fatal: [localhost]: FAILED! => {"changed": false, "msg": "No package matching 'php7.1-yaml' is available"}

Summary

See failed build: https://travis-ci.org/geerlingguy/drupal-vm/jobs/426719440

I'm guessing there was an upstream change in the repo and maybe that package was removed. We could either switch to Debian 9, or switch to 7.2 or 7.0.