Change log for VMWARE_ESX

Date Changes
2022-05-02 Bugfix - As per the user requirement, target.hostname mapping changed to principal.ip for the logs which have service as "Hostd".
2022-04-13 Enhancement-Parsed the logs having the following service names: hostd-probe, vmkernel, vmkwarning, Fdm, netcpa, root, hpHelper, snmpd, etc.
Mapped logstash.ingest.timestamp to metadata.ingested_timestamp,
logstash.ingest.host and logstash.process.host to intermediary.hostname,
logstash.collect.host to observer.hostname.