Add handling of /health endpoint support to inputs.influxdb_v2_listener

[andrasg]

Use Case

I am trying to create a telegraf inputs.influxdb_v2_listener to receive metrics from Proxmox. I am unable to do so, as Proxmox considers the target unhealthy due to receiving 404 not found when calling the /health endpoint.

See influx API docs: https://docs.influxdata.com/influxdb/v2/api/#operation/GetHealth

The input plugin already serves a /ready endpoint: https://github.com/influxdata/telegraf/blob/master/plugins/inputs/influxdb_v2_listener/influxdb_v2_listener.go#L225

Expected behavior

inputs.influxdb_v2_listener plugin should respond with 200 OK to the /health endpoint when healthy.

Actual behavior

inputs.influxdb_v2_listener plugin responds with 404 not found when accessing the /health endpoint.

Additional info

No response