picocli-codegen generates invalid reflect.json for inner classes

[remkop]

When a command has an inner class, like an inner enum, the generated reflect.json contains the name of the enum twice, once as Outer$Inner, and once again as Outer.Inner.

This latter entry gives an error in native-image:

$ native-image -cp .:picocli-4.1.2.jar Outer
Build on Server(pid: 199, port: 57471)
[filelist:199]    classlist:     407.24 ms
[filelist:199]        (cap):   3,680.55 ms
[filelist:199]        setup:   4,259.75 ms
Error: Error parsing reflection configuration in file:/home/remko/project/META-INF/native-image/picocli-generated/reflect-config.json:
Class Outer.Inner not found