Change log for IBM_SAM

Date Changes
2024-03-08 Enhancement:
- Added support for new pattern of syslog logs.
- Mapped "src_host" to "principal.hostname" and "principal.asset.hostname".
- Mapped "src_port" to "principal.port".
- Mapped "user_name" to "principal.user.userid".
- Mapped "src_application" to "principal.application".
- Mapped "product_event_type" to "metadata.product_event_type".
- Mapped "description" to "metadata.description".
- Mapped "target_hostname" to "target.hostname".
- Mapped "src_resource" to "principal.resource.name".
- Mapped "severity" to "security_result.severity".
- Mapped "pid" to "principal.process.pid".
- Mapped "file_name" to "principal.file.full_path".
- Mapped "connection_type" to "additional.fields".
- Aligned mappings for "principal.ip" and "principal.asset.ip".
- Aligned mappings for "target.ip" and "target.asset.ip".
2023-09-12 Enhancement:
- Added a Grok pattern to support new log format.
2023-05-21 Newly created parser.