[BUG][Dart] dioNext: BuiltList<String> gets brackets in query string

Created by: markbeij

openapi-generator version

openapi_generator: ^3.1.3

OpenAPI declaration file content or url

https://petstore.swagger.io/#/pet/findPetsByStatus

Generation Details

flutter pub run build_runner build --delete-conflicting-outputs

@Openapi(
    additionalProperties: AdditionalProperties(pubName: 'petstore_api_client', pubAuthor: 'www.blah.com'),
    inputSpecFile: 'https://petstore.swagger.io/v2/swagger.json',
    generatorName: Generator.dioNext,
    outputDirectory: '../petstore',
    overwriteExistingFiles: true,
    alwaysRun: true)
class ShuttelApiClientGeneratorConfig extends OpenapiGeneratorConfig {}

Steps to reproduce

Generate client using Generator.dioNext
Execute unit test: https://gist.github.com/markbeij/c23b32d4dbda7477ff673f2b3f9e827a.js

Expected url is: https://petstore.swagger.io/v2/pet/findByStatus?status=available But got: https://petstore.swagger.io/v2/pet/findByStatus?status=%5Bavailable%5D