The role doesn't work with ansible 2.7.18 :
```
TASK [prometheus : prometheus | include asserts] **************************************************************************************************************
fatal: [host]: FAILED! => {"reason": "no action detected in task. This often indicates a misspelled module name, or incorrect module path.\n\nThe error appears to have been in '/usr/local/ansible/orchestrator/roles/prometheus/tasks/asserts.yml': line 9, column 3, but may\nbe elsewhere in the file depending on the exact syntax problem.\n\nThe offending line appears to be:\n\n\n- name: 'prometheus | assert | gather the package facts'\n ^ here\n"}
```
Ansible 2.8.20 is OK.
