As of ClamAV 0.103.2 the SafeBrowsing config option was deprecated. See here for more information. To fix the error edit the file freshclam.conf and comment out the SafeBrowsing line in the config file. You can use the command:
sed -i -e "s/^SafeBrowsing /#SafeBrowsing /" /etc/freshclam.conf
sed -i -e "s/^SafeBrowsing /#SafeBrowsing /" /etc/clamav/freshclam.conf
This has been fixed in Warden 2.08-1 and Sentinel 1-14-1 which was published to the Plesk extension directory.