Change log for ELASTIC_PACKETBEATS

Date Changes
2024-03-23 Enhancement:
- Mapped "headers.accept_encoding" and "headers.x_envoy_attempt_count" to "security_result.about.labels".
- Mapped "headers.content_length", "headers.content_type", "headers.x_forwarded_proto", "headers.x_b3_sampled", "headers.http_accept", "headers.x_b3_parentspanid", "headers.x_envoy_original_path", "client_cert" and "headers.x_request_id" to "additional.labels".
- Mapped "headers.http_user_agent" to "network.http.user_agent".
- Mapped "headers.request_method" to "network.http.method".
- Mapped "dns.resolved_ip" to "network.dns.additional".
- Mapped "headers.http_host" to "principal.hostname".
- Mapped "headers.x_forwarded_for" and "host" to "principal.ip"
2022-05-09 Added mapping for server_name, application, user_id, user_name, level, msg, logger, audit_category, audit_cluster_name, audit_node_id, audit_node_name, audit_request_effective_user, component, uuid.
2022-04-12 Added generic string for Vendor name and replaced different product names to a generic value string.