[Kotlin][Client] Enum toString handling

Created by: AlexanderEggers

I have noticed that in certain cases, the enum usage for path parameter and url query parameter is incorrectly implemented.

In the case I have an enum with MY_ENUM("MyEnum") and I am using the enum as a path parameter. The path would look like that "myPath/.../MY_ENUM/...". This request would always fail. That is due to the different enum value than the server would expect.

To fix this issue, I suggest we add a custom toString to every enum class so that we will not use the enum var name but the value. That way the path would look like this "myPath/.../MyEnum/...".

Changes made with this PR:

• Added custom toString to the enum class script.

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