This is the `ccr` metricset of the {es} module. It uses the
Cross-Cluster Replication Stats API endpoint to fetch metrics about cross-cluster
replication from the {es} clusters that are participating in cross-cluster
replication.

If the {es} cluster does not have cross-cluster replication enabled, this metricset
will not collect metrics. A DEBUG log message about this will be emitted in the
Metricbeat log.
