OpenAPI generator : Blank enum is not correctly generated

[AdrienMDevMobile]

Blank enum class is not correctly generated for the Kotlin project

The correction can easily be hand made : AdrienMDevMobile/openfoodfactApiKotlin@3c03b41#diff-8c6fe083fc223506054754bf477a90bfd717bd17bdc577d669d1dfaf0a39ef82R29

But I will look at how to not have to hand made fix it and rather fixe directly the openAPI
For instance : https://stackoverflow.com/questions/73244706/spring-boot-openapi-swagger-enums-with-empty-strings-generates-empty-inste

[AdrienMDevMobile]

This generated error is tightly connected to #522 (comment) because classes using oneOf are the only affected by this issue.