Swagger-codegen for sharp not properly calling base constructor for enum in superclass

Description

When I use swagger-codegen to generate a client in sharp using the Json seen in the gist below It does not property set the errorcode in the constructor for the Response[SomeDTO] class, but instead generates the following:

public ResponseImageDTO(bool? success = default(bool?), List<string> errorProperties = default(List<string>), string response = "Response[ImageDTO]") : base(success, errorProperties, errorKey, response) { }

As you can see the errorKey is never set in the constructor only in the call to the constructor of the superclass thus resulting in a syntax error.

If I in the response class change errorkey to the following:

"errorKey":{  
   "$ref":"#/definitions/ErrorCode",
   "readOnly":true
}

Then by using swagger-codegen 2.3.1 it generates the constructor properly but not by using the newest version on master.

However what I would like is that I don't have to ref to the ErrorKey in order for it to be set correctly in the generated constructor.

Swagger declaration content

Small sample:
https://gist.github.com/Flarenityy/ace43932311c9939e96c1af04f0dbaf3

Full sample (however it is huge so I would suggest u look above)
https://gist.github.com/Flarenityy/cacf31288da8db5ae86a65699968eb67

Command line used for generation

java -jar modules/swagger-codegen-cli/target/swagger-codegen-cli.jar generate -i http://localhost:5000/swagger/v1/swagger.json -l csharp

Start with the small Swagger declaration in the linked gist and reproduce generation using modules/swagger-codegen-cli/target/swagger-codegen-cli.jar with the csharp language option. Inspect how the generated Response[SomeDTO] constructor handles the inherited enum property. Done means the generated constructor initializes errorKey correctly without requiring an explicit ErrorCode reference and produces valid C#.