Currently Dockerfile builds can't enable offline builds as some Maven plugin dependencies are not correctly loaded by `./mvnw dependency:resolve-plugins dependency:go-offline initialize -B`.

Enable Dockerfile Maven offline builds with adding `-o` parameter, like:
`./mvnw clean package -o -B -am -pl backend -Dmaven.wagon.http.pool=false -Dmaven.wagon.httpconnectionManager.ttlSeconds=120`