try

Author: trask

smoke-tests/images/quarkus/build.gradle.kts

@@ -35,6 +35,7 @@ jib {
   pluginExtensions {
     pluginExtension {
       implementation = "com.google.cloud.tools.jib.gradle.extension.quarkus.JibQuarkusExtension"
+      properties["packageType"] = "fast-jar"
     }
   }
 }