I was just able to recreate this when I added a folder called 'test' and it created an 'editor' folder upon export. Here's everything zipped up just in case it would help to look at it.
When I export that project, there is no editor folder.
Add another folder via Resources, save and export.
Tried that too.
The only way I can replicate it is with the duplicate name. However once we fix that, I am sure it will correct other ways it might be found.