add openmetrics health to metrics csv file

Author: RTJL

grafana/metadata.csv

@@ -210,6 +210,7 @@ grafana.live_node_num_users,gauge,,,,Number of unique users connected.,0,grafana
 grafana.live_node_pub_sub_lag_seconds.bucket,count,,second,,Pub sub lag in seconds,0,grafana,,,
 grafana.live_node_pub_sub_lag_seconds.count,count,,second,,Pub sub lag in seconds,0,grafana,,,
 grafana.live_node_pub_sub_lag_seconds.sum,count,,second,,Pub sub lag in seconds,0,grafana,,,
+grafana.openmetrics.health,gauge,,,,Whether the check is able to connect to the metrics endpoint.,0,grafana,,,
 grafana.page_response_status.count,count,,,,page http response status,0,grafana,,,
 grafana.plugin_build_info,gauge,,,,"A metric with a constant '1' value labeled by pluginId, pluginType and version from which Grafana plugin was built",0,grafana,,,
 grafana.plugin_target_info,gauge,,,,A metric with a constant '1' value labeled by pluginId and target,0,grafana,,,