Do not assume DynamicHub.module is always non-null.

Author: olpaw

substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/hub/DynamicHub.java

@@ -714,7 +714,7 @@ public Enum<?>[] getEnumConstantsShared() {
 
     @Substitute
     public InputStream getResourceAsStream(String resourceName) {
-        String moduleName = SubstrateUtil.cast(module, Target_java_lang_Module.class).name;
+        String moduleName = module == null ? null : SubstrateUtil.cast(module, Target_java_lang_Module.class).name;
         String resolvedName = resolveName(resourceName);
         return Resources.createInputStream(moduleName, resolvedName);
     }