RunnerClassLoader.findResources does return null

[moritz-bruder]

quarkus/independent-projects/bootstrap/runner/src/main/java/io/quarkus/bootstrap/runner/RunnerClassLoader.java

Line 196 in ba778a7

return null;

In the javadoc of the official API of java/lang/ClassLoader.findResources it is mentioned that this method will always return an Enumeration. While OpenJDK does protect against null this is by no means a requirement. In order to increase robustness and compatibility with other VMs, it is best to not return null or at least not in this specific inherited method.

[jaikiran]

I've opened #15634 to include this change.