[BUG] Models of generator "jaxrs-spec" are missing `@Generated` annotations

[ChristianCiach]

Bug Report Checklist

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Description

When using the generator "jaxrs-spec", the generated model classes are missing @Generated annotations even when the generator option hideGeneratedTimestamp is set to false. The generated api-interface is annotated correctly.

openapi-generator version

Gradle plugin "org.openapi.generator" version "4.1.2".

Command line used for generation

Gradle configuration of the GenerateTask object:

  generatorName = "jaxrs-spec"
  inputSpec = "myspec.yaml"  
  outputDir = "myoutputDir"
  apiPackage = "my.package.api"
  modelPackage = "my.package.model"
  configOptions = [
    dateLibrary: "java8",
    interfaceOnly: "true",
    returnResponse: "true",
    generatePom: "false",
    useTags: "true",
    hideGenerationTimestamp: "false"
  ]