Change log for CISCO_UNITY_CONNECTION

Date Changes
2025-05-15 - Added grok patterns to support a new format of syslog logs.
- Added new date patterns to parse event.idm.read_only_udm.metadata.event_timestamp UDM field.
- Added support for handling HKT timezone for event.idm.read_only_udm.metadata.event_timestamp UDM field.
- event.idm.read_only_udm.security_result.summary: Newly mapped sec_sum raw log field with event.idm.read_only_udm.security_result.summary UDM field.
2024-10-17 Newly created parser.