[BUG] [C#] [Client] Code not generated properly for deep alias

[Mattias-Sehlstedt]

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator?
• Have you tested with the latest master to confirm the issue still exists?
• Have you searched for related issues/PRs?
• What's the actual output vs expected output?
• [Optional] Sponsorship to speed up the bug fix or feature request (example)

Description

Sub-issues from issue 21585 where invalid code is generated due to the schema containing a deep alias. Example is
GeoJSONMultiLineString(TypeEnum type, List<List<List>> for the schema with the title GeoJSON MultiLineString in the specification below.

openapi-generator version

OpenAPI declaration file content or url

openapi: 3.0.3
info:
  title: weather.gov API
  description: weather.gov API
  version: 2.5.1
servers:
  - url: https://api.weather.gov
    description: Production server
paths:
  /alerts/active/zone/{zoneId}:
    get:
      description: Returns active alerts for the given NWS public zone or county
      operationId: alerts_active_zone
      responses:
        '200':
          $ref: '#/components/responses/AlertCollection'
      parameters: []
    parameters:
      - $ref: '#/components/parameters/NWSZoneId'
components:
  schemas:
    GeoJsonBoundingBox:
      minItems: 4
      type: array
      items:
        type: number
      description: A GeoJSON bounding box. Please refer to IETF RFC 7946 for information on the GeoJSON format.
    GeoJsonCoordinate:
      minItems: 2
      type: array
      items:
        type: number
      description: A GeoJSON coordinate. Please refer to IETF RFC 7946 for information on the GeoJSON format.
    GeoJsonGeometry:
      oneOf:
        - title: GeoJSON Point
          required:
            - type
            - coordinates
          type: object
          properties:
            type:
              enum:
                - Point
              type: string
            coordinates:
              $ref: '#/components/schemas/GeoJsonCoordinate'
            bbox:
              $ref: '#/components/schemas/GeoJsonBoundingBox'
        - title: GeoJSON LineString
          required:
            - type
            - coordinates
          type: object
          properties:
            type:
              enum:
                - LineString
              type: string
            coordinates:
              $ref: '#/components/schemas/GeoJsonLineString'
            bbox:
              $ref: '#/components/schemas/GeoJsonBoundingBox'
        - title: GeoJSON Polygon
          required:
            - type
            - coordinates
          type: object
          properties:
            type:
              enum:
                - Polygon
              type: string
            coordinates:
              $ref: '#/components/schemas/GeoJsonPolygon'
            bbox:
              $ref: '#/components/schemas/GeoJsonBoundingBox'
        - title: GeoJSON MultiPoint
          required:
            - type
            - coordinates
          type: object
          properties:
            type:
              enum:
                - MultiPoint
              type: string
            coordinates:
              type: array
              items:
                $ref: '#/components/schemas/GeoJsonCoordinate'
            bbox:
              $ref: '#/components/schemas/GeoJsonBoundingBox'
        - title: GeoJSON MultiLineString
          required:
            - type
            - coordinates
          type: object
          properties:
            type:
              enum:
                - MultiLineString
              type: string
            coordinates:
              type: array
              items:
                $ref: '#/components/schemas/GeoJsonLineString'
              description: "A GeoJSON MultiLineString"
            bbox:
              $ref: '#/components/schemas/GeoJsonBoundingBox'
        - title: GeoJSON MultiPolygon
          required:
            - type
            - coordinates
          type: object
          properties:
            type:
              enum:
                - MultiPolygon
              type: string
            coordinates:
              type: array
              items:
                $ref: '#/components/schemas/GeoJsonPolygon'
            bbox:
              $ref: '#/components/schemas/GeoJsonBoundingBox'
      description: A GeoJSON geometry object. Please refer to IETF RFC 7946 for information on the GeoJSON format.
      nullable: true
    GeoJsonFeature:
      required:
        - type
        - geometry
        - properties
      type: object
      properties:
        type:
          enum:
            - Feature
          type: string
        geometry:
          $ref: '#/components/schemas/GeoJsonGeometry'
        properties:
          type: object
      description: A GeoJSON feature. Please refer to IETF RFC 7946 for information on the GeoJSON format.
      additionalProperties: false
    GeoJsonFeatureCollection:
      required:
        - type
        - features
      type: object
      properties:
        type:
          enum:
            - FeatureCollection
          type: string
        features:
          type: array
          items:
            $ref: '#/components/schemas/GeoJsonFeature'
      description: A GeoJSON feature collection. Please refer to IETF RFC 7946 for information on the GeoJSON format.
    GeoJsonLineString:
      minItems: 2
      type: array
      items:
        $ref: '#/components/schemas/GeoJsonCoordinate'
      description: A GeoJSON line string. Please refer to IETF RFC 7946 for information on the GeoJSON format.
    GeoJsonPolygon:
      type: array
      items:
        minItems: 4
        type: array
        items:
          $ref: '#/components/schemas/GeoJsonCoordinate'
      description: A GeoJSON polygon. Please refer to IETF RFC 7946 for information on the GeoJSON format.
    NWSZoneID:
      pattern: ^(A[KLMNRSZ]|C[AOT]|D[CE]|F[LM]|G[AMU]|I[ADLN]|K[SY]|L[ACEHMOS]|M[ADEHINOPST]|N[CDEHJMVY]|O[HKR]|P[AHKMRSWZ]|S[CDL]|T[NX]|UT|V[AIT]|W[AIVY]|[HR]I)[CZ]\d{3}$
      type: string
      description: |
        UGC identifier for a NWS forecast zone or county.
        The first two letters will correspond to either a state code or marine area code (see #/components/schemas/StateTerritoryCode and #/components/schemas/MarineAreaCode for lists of valid letter combinations).
        The third letter will be Z for public/fire zone or C for county.
  responses:
    AlertCollection:
      description: A collection of alerts.
      content:
        application/geo+json:
          schema:
            $ref: '#/components/schemas/GeoJsonFeatureCollection'
      x-url-content-negotiation-extensions:
        json: application/geo+json
        atom: application/atom+xml
  parameters:
    NWSZoneId:
      name: zoneId
      in: path
      description: NWS public zone/county identifier
      required: true
      schema:
        $ref: '#/components/schemas/NWSZoneID'
externalDocs:
  description: Full API documentation
  url: https://www.weather.gov/documentation/services-web-api

Generation Details

Steps to reproduce

Related issues/PRs

21585

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