Change log for FORTINET_FORTIMAIL

Date Changes
2026-05-27 Enhancement:
- Added new grok pattern to parse the raw logs.
- `event.idm.read_only_udm.target.url`: Newly mapped `url` raw log field with `event.idm.read_only_udm.target.url` UDM field.
- `event.idm.read_only_udm.additional.fields`: Newly mapped `syslog_priority` raw log field with `event.idm.read_only_udm.additional.fields UDM field.
2025-02-25 Enhancement:
- Mapped "type" and "subtype" to "metadata.product_event_type".
- Mapped "to" to "network.email.to".
2023-09-06 Enhancement:
- Added a Grok pattern to extract the data and parse failing KV logs.
2023-05-23 - New parser.