IllegalArgumentException from ASM

Experiencing this issue when trying to Jib up the Groovy project at https://github.com/coollog/skaffold-code.one/tree/master/frontend-service

```
* What went wrong:
Execution failed for task ':jib'.
> java.lang.IllegalArgumentException (no error message)

* Try:
Run with --info or --debug option to get more log output. Run with --scan to get full insights.

* Exception is:
...
Caused by: java.lang.IllegalArgumentException
at org.objectweb.asm.ClassVisitor.(ClassVisitor.java:79)
at org.objectweb.asm.ClassVisitor.(ClassVisitor.java:64)
at com.google.cloud.tools.jib.frontend.MainClassFinder$MainClassVisitor.(MainClassFinder.java:123)
at com.google.cloud.tools.jib.frontend.MainClassFinder$MainClassVisitor.(MainClassFinder.java:111)
at com.google.cloud.tools.jib.frontend.MainClassFinder.findMainClass(MainClassFinder.java:190)
at com.google.cloud.tools.jib.frontend.MainClassFinder.find(MainClassFinder.java:161)
at com.google.cloud.tools.jib.plugins.common.MainClassResolver.findMainClassInClassFiles(MainClassResolver.java:129)
at com.google.cloud.tools.jib.plugins.common.MainClassResolver.resolveMainClass(MainClassResolver.java:61)
at com.google.cloud.tools.jib.plugins.common.PluginConfigurationProcessor.computeEntrypoint(PluginConfigurationProcessor.java:278)
at com.google.cloud.tools.jib.plugins.common.PluginConfigurationProcessor.processCommonConfiguration(PluginConfigurationProcessor.java:208)
at com.google.cloud.tools.jib.plugins.common.PluginConfigurationProcessor.processCommonConfigurationForRegistryImage(PluginConfigurationProcessor.java:155)
at com.google.cloud.tools.jib.gradle.BuildImageTask.buildImage(BuildImageTask.java:104)
at org.gradle.internal.reflect.JavaMethod.invoke(JavaMethod.java:73)
at
...
```