Prevent shutdown so jbom can finish analyzing short-lived processes

[planetlevel]

          Hmm... not sure if there's a good way to do that.  Maybe jbom add a shutdown hook that would wait until jbom is finished.  Anyone want to try implementing this?  https://www.baeldung.com/jvm-shutdown-hooks

Originally posted by @planetlevel in https://github.com/eclipse/jbom/issues/11#issuecomment-1411080982