libbeat licenser error references /_xpack endpoint

[inqueue]

• Version: 7.6.2 + master
• Operating System: n/a
• Discuss Forum URL: n/a
• Steps to Reproduce: Force the licenser callback into an error, like breach the parent circuit breaker on the cluster. In this case, the error was produced by having indices.breaker.total.limit set too low in the cluster.

While attempting to troubleshoot a cluster connection issue with Filebeat, I noticed this error references the /_xpack endpoint when it actually uses the /_license endpoint.

Apr 20 16:08:18 beat.host.name filebeat[5515]: 2020-04-20T16:08:18.309-0400        ERROR        elasticsearch/elasticsearch.go:261        Error connecting to Elasticsearch at http://cluster.host.name:9200: Connection marked as failed because the onConnect callback failed: cannot retrieve the elasticsearch license from the /_xpack endpoint, Filebeat requires the default distribution of Elasticsearch. Please make the endpoint accessible to Filebeat so it can verify the license.: could not retrieve the license information from the cluster: 429 Too Many Requests: {"error":{"root_cause":[{"type":"circuit_breaking_exception","reason":"[parent] Data too large, data for [<http_request>] would be [3044232488/2.8gb], which is larger than the limit of [2978584985/2.7gb], real usage: [3044232488/2.8gb], new bytes reserved: [0/0b], usages [request=0/0b, fielddata=0/0b, in_flight_requests=0/0b, accounting=0/0b]","bytes_wanted":3044232488,"bytes_limit":2978584985,"durability":"TRANSIENT"}],"type":"circuit_breaking_exception","reason":"[parent] Data too large, data for [<http_request>] would be [3044232488/2.8gb], which is larger than the limit of [2978584985/2.7gb], real usage: [3044232488/2.8gb], new bytes reserved: [0/0b], usages [request=0/0b, fielddata=0/0b, in_flight_requests=0/0b, accounting=0/0b]","bytes_wanted":3044232488,"bytes_limit":2978584985,"durability":"TRANSIENT"},"status":429}

The error caused some initial confusion since A) there is an error, and B) /_xpack is no longer used. It'd be best if the endpoint were not hardcoded in the error-- I'll leave that up to you. Can it at least not reference /_xpack?

See also #15090.

[elasticmachine]

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