Monitor if isobuilders systems are running fine

Originally created by @bertagaz on #11858 (Redmine)

We experienced times where our isobuilders were slowly getting all down when a branch was triggering the OOM during its build.

We should use our monitoring system to check using systemd and/or anything else if the isobuilders systems are running fine, so that we know if we have to restart them or their jenkins-slave service.

Feature Branch: puppet-tails:feature/11858-monitor-systemd

Related issues

Edited by bertagaz