[Kotlin][BUG] Fix enum properties in requests

Created by: tihonovgn

The request contains an enum key instead of a value when specifying an enum type for a request field in the specification

Specification:

/jwt-generate-claims/rs256/1:
  post:
    operationId: generateJwt
    description: Create order api
    requestBody:
      required: true
      content:
        application/x-www-form-urlencoded:
          schema:
            type: object
            required:
              - audience
            properties:
              audience:
                type: string
                enum:
                  - "A333!"

Generated enum:

enum class Audience_generateJwt(val value: kotlin.String) {
    @Json(name = "A333!") a333Exclamation("A333!")
}

request.body contains audience=a333Exclamation instead of audience=A333!

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[Kotlin][BUG] Fix enum properties in requests

The request contains an enum key instead of a value when specifying an enum type for a request field in the specification

Bug Report Checklist

Description

openapi-generator version

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