Error in build for docker image and mvn install

[dgarijo]

There are currently two issues:

• The dockerfile does not work anymore, because the docker.io/library/openjdk:17-slim image is no longer available. This will have to be replaced with a new image.
• The test ExternalEntities does not work anymore @vChavezB I have commented it out, please have a look if you have the time

[vChavezB]

@dgarijo I have fixed the issue, please refer to vChavezB#15

[dgarijo]

Thanks! Leaving the issue open until I fix the image problem