remove <version>1.5.5 from mariadb-java-client which bumps it to 2.2.3
remove <version>1.5.5 from mariadb-java-client which bumps it to 2.2.3

The artifact is managed in
org.springframework.boot:spring-boot-dependencies:2.0.2.RELEASE
vorburger/MariaDB4j,vorburger/MariaDB4j