replace backend base image

[GGoetzelmann]

The openjdk 17 base image currently in use has quite a lot of severe vulnerabilities and should be replaced

https://hub.docker.com/layers/library/openjdk/17-jdk-slim/images/sha256-d732b25fa8a6944d312476805d086aeaaa6c9e2fbc3aefd482b819d5e0e32e10

Moreover, while it contains a tag for arm64, it still may cause emulation issues on Mac M3 processors.
Not sure if the base image is at fault here or if the according architecture tag is simply missing from the backend image: https://hub.docker.com/r/vitalie97/mapping-service-backend/tags

But I think we replaced a related image for the base-repo with https://hub.docker.com/_/eclipse-temurin images for at least similar reasons.