Thanks for reporting. Somehow, the tests for janusgraph-examples do not pass anymore when run in a stand-alone fashion (these tests are also run in the CI from the main pom.xml in https://github.com/JanusGraph/janusgraph/blob/master/pom.xml , where obviously they do pass). I reported an issue for this. https://github.com/JanusGraph/janusgraph/issues/2911

If you just want to run the examples you can build the jar with:

mvn clean install -DskipTests

Best wishes,     Marc