Change log for ORACLE_DB

Date Changes
2022-08-01 Enhancement: Added mapping for following fields:
- "hostname" mapped to "principal.hostname".
- if "returncode" is "0" then security_result.action mapped to "ALLOW" else if it is "-1" then mapped to "BLOCK"
- "ACTION" mapped to "metadata.product_event_type".
- "DATABASE USER" mapped to "principal.user.user_display_name".
- "PRIVILEGE" mapped to "principal.user.attribute.permissions".
- "CLIENT USER" mapped to "target.user.user_display_name".
- "file_name" mapped to "target.file.full_path".
- "event_name" mapped to "metadata.product_event_type".
- "ACTION_NUMBER" mapped to "event.idm.read_only_udm.additional.fields".
- "length" mapped to "event.idm.read_only_udm.additional.fields".
- "DBID" mapped to "metadata.product_log_id".