DartError: TypeError: null: type 'Null' is not a subtype of type 'Map<String, dynamic>'

[gonft]

Steps to reproduce

1. Launch the web interface (https://carapacik.github.io/swagger_parser)
2. Tap Generate and download

Expected results

Generate code

Actual results

Failed to generate files.
    type 'Null' is not a subtype of type 'Map<String, dynamic>' in type cast
    #0      OpenApiParser.parseRestClients.parametersV3 (package:swagger_parser/src/parser/parser/open_api_parser.dart:365:49)
    #1      OpenApiParser.parseRestClients.<anonymous closure>.<anonymous closure> (package:swagger_parser/src/parser/parser/open_api_parser.dart:583:15)
    #2      _LinkedHashMapMixin.forEach (dart:collection-patch/compact_hash.dart:633:13)
    #3      OpenApiParser.parseRestClients.<anonymous closure> (package:swagger_parser/src/parser/parser/open_api_parser.dart:567:17)
    #4      _LinkedHashMapMixin.forEach (dart:collection-patch/compact_hash.dart:633:13)
    #5      OpenApiParser.parseRestClients (package:swagger_parser/src/parser/parser/open_api_parser.dart:554:10)
    #6      GenProcessor.generateFiles (package:swagger_parser/src/generator/generator/generator_processor.dart:32:32)
    <asynchronous suspension>
    #7      main (file:///Users/paul/.pub-cache/hosted/pub.dev/swagger_parser-1.19.2/bin/swagger_parser.dart:22:39)
    <asynchronous suspension>

Your OpenApi snippet

openapi: 3.0.3
info:
  title: API Document
  description: Swagger UI를 이용한 API 문서입니다.
  license:
    name: MIT License
  version: 1.0.0
servers:
- url: /
paths:
  /api/v1/members/agreements/agree:
    post:
      tags:
      - 온보딩
      summary: 약관 동의
      description: "\n            약관 동의\n            "
      operationId: api_v1_members_agreements_agree_create
      parameters:
      - name: Authorization
        in: header
        description: "Bearer {token} 형태로 값을 넣습니다. Swagger에서 테스트 하기 위해서는 상단에 Authorize\
          \ 버튼을 이용합니다."
        required: true
        style: simple
        explode: false
        schema:
          type: string
      requestBody:
        content:
          application/json:
            schema:
              type: array
              items:
                $ref: '#/components/schemas/MemberAgreement'
          application/x-www-form-urlencoded:
            schema:
              type: array
              items:
                $ref: '#/components/schemas/MemberAgreement'
          multipart/form-data:
            schema:
              type: array
              items:
                $ref: '#/components/schemas/MemberAgreement'
        required: true
      responses:
        "200":
          description: Simple response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/SimpleResponse'
              examples:
                Success:
                  value:
                    status: Success
                    message: 요청이 성공했습니다.
      security:
      - tokenAuth: []
      - {}
components:
  schemas:
    MemberAgreement:
      required:
      - agreement_id
      type: object
      properties:
        agreement_id:
          maximum: 9223372036854775807
          minimum: -9223372036854775808
          type: integer
          format: int64
        agreed:
          type: boolean
    SimpleResponse:
      required:
      - message
      - status
      type: object
      properties:
        status:
          type: string
        message:
          type: string
  securitySchemes:
    tokenAuth:
      type: apiKey
      description: Token-based authentication with required prefix "Token"
      name: Authorization
      in: header