Make Irker service check supported_events
63178a9509 added the supported_events check for services. Since f84b7eef3f was just added, we should adjust it accordingly.
See merge request !367
Irker is a gateway which sends IRC messages on git updates. This new
service provides an interface to this gateway, integrated in Gitlab, for
each updates.
As per the guidelines, this commit adds the new feature in the
CHANGELOG, tests and documentation.
See http://www.catb.org/esr/irker/