The default rabbitmq image disables metrics collection via the management
api. This is implemented by adding a file named:
/etc/rabbitmq/conf.d/management_agent.disable_metrics_collector.conf
with the contents:
management_agent.disable_metrics_collector = true
The prometheus exporter currently used by osh requires this value to be
false.
This change was introduced when rabbit introduced the integrated
prometheus exporter:
https://github.com/docker-library/rabbitmq/issues/419
Change-Id: I9a94f49a7827bb4725ed3fd98404e637bfefa086
5cbce03f21