Log persistence is enabled by default when storage is configured

I've just noticed my storage device is receiving the logs via the storage plugin even though I never opted for that. For long, I have a custom logging logic on the storage device configured directly in syslog-ng, so there's no reason for the log persistence via Reforis.

My /etc/config/storage did not contain the syslog key at all, so I thought the persistence was off. However, in the Reforis GUI, it showed up as turned on, and the logs were actually saved to /srv/log.

The culprit is the default here: https://gitlab.nic.cz/turris/foris-controller/foris-controller-storage-module/-/blob/master/scripts/syslog-ng.sh#L6

Please, change the default to disabled as the current default can have unintended consequences for many people.