Issue update plesk 18.0.20

[lesny]

Hello I can not update 18.0.20 from plesk here is the error message


===> Upgrading database

Trying to start service mysql... /usr/sbin/mysqld (pid 730) is running...
done
Trying to establish test connection... /usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
/usr/bin/mysql: unknown variable ''mysql.utf8mb4'=> true,'
failed

ERROR while trying to establish test connection

Check the error reason (see log file: /var/log/plesk/install/plesk_18.0.20_installation.log), fix and try again
***** problem report *****
ERROR while trying to establish test connection
Error: Une erreur s'est produite lors de l'exécution des actions PREP installation (voir le log pour en savoir plus). L'installation a été annulée.
Attention ! Les packages n'ont pas tous été installés.
Merci de contrôler si vos services système sont utilisables.
Résolvez le problème et réessayez d'installer les packages. Visitez Plesk Help Center pour trouver une solution.