[MPESW-426] java-server on systemd (and tiny tweaks on filebeat and metricbeat)

Context

• https://its.cern.ch/jira/browse/PM-434
• Move the ansible java-server from monit to systemd

What was done

• Removed references to monit mechanics (e.g. monit, pid file, etc.). hopefully I got them all

TODO

• Hopefully No

QA

• N/A

Review objectives

• assess functionality
• knowledge sharing