Java S2I image: terrible error message with multiple JARs in /deployments

(This comes from OBST-55.)

I'm using the latest Red Hat OpenShift Java S2I image (registry.access.redhat.com/redhat-openjdk-18/openjdk18-openshift:latest) to run a WildFly Swarm project. Under some circumstances, it may happen that 2 JARs appear in /deployments in the built image. In such case, the run-java.sh script gets confused and prints a really terrible error message:

Starting the Java application using /opt/run-java/run-java.sh ...
/opt/run-java/run-java.sh: line 44: cd: /home/jboss: Permission denied

To reproduce, download the attached reproducer.yml, run oc apply -f reproducer.yml, then oc start-build foobar and then watch the pod log.

I looked into the run-java.sh script and I kinda understand why this happens, but the issue really is in that there are 2 JARs in /deployments which they shouldn't. But figuring out that this is the issue requires carefully inspecting the run-java.sh script, which is time-consuming and highly unfriendly. Maybe the script could print a warning message before looking in /home/jboss?

(BTW, this could also possibly happen with Spring Boot, see OBST-273.)