Change log for ZSCALER_TUNNEL

Date Changes
2026-01-06 - Updated the field mapping for the Zscaler Tunnel parser. Please refer to the parser documentation page for information regarding the updated UDM mappings - https://docs.cloud.google.com/chronicle/docs/ingestion/default-parsers/zscaler-tunnel#udm_mapping_delta
2025-06-04 - Adding support for the legacy log format in the ZSCALER_TUNNEL parser.
2025-04-30 - Promoted ZSCALER_TUNNEL Premium parser to default. You can see full details in the parser configuration page - https://cloud.google.com/chronicle/docs/ingestion/default-parsers/ingest-zscaler-logs