"WARNING: Configuration file format is too old" message seen during the reboot after upgrading the PAN-OS version to 10.2 or 11.0

Starting syslog-ng-system:[2023-05-10T00:00:45.963448] WARNING: Configuration file format is too old, syslog-ng is running in compatibility mode. Please update it to use the syslog-ng 3.29 format at your time of convenience. To upgrade the configuration, please review the warnings about incompatible changes printed by syslog-ng, and once completed change the @version header at the top of the configuration file; config-version='3.9'
[2023-05-10T00:00:46.116803] WARNING: log-fifo-size() works differently starting with syslog-ng 3.22 to avoid dropping flow-controlled messages when log-fifo-size() is misconfigured. From now on, log-fifo-size() only affects messages that are not flow-controlled. (Flow-controlled log paths have the flags(flow-control) option set.) To enable the new behaviour, update the @version string in your configuration and consider lowering the value of log-fifo-size().;