Change log for CHECKPOINT_EDR

Date Changes
2022-09-07 Enhancement- Parsed logs with event_type as "empty".
- mapped "client_ip" to "event.edr.network.target_ip".
- mapped "origin" to "event.edr.network.target_ip" if client_ip empty.
- mapped "subject" to "event.edr.task.task_name".
- mapped "host_name" to "event.edr.client.hostname".
- mapped "ifdir" to "event.edr.network.direction".