[BUG] [typescript-fetch] object types should not be marked as object types in typescript

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
• What's the version of OpenAPI Generator used?
• Have you search for related issues/PRs?
• What's the actual output vs expected output?
• [Optional] Bounty to sponsor the fix (example)

Description

Given a property that is labeled as type: object in the openapi spec, and no extra restrictions, the typescript generator produces a parameter with type signature object. In the openapi spec, object with no extra restrictions/parameters, or with additionalProperties: true set, denotes any valid object with any extra properties. This should be declared in typescript as the any type.

This is an issue because now it's impossible to reference a key from the object type in typescript. For example, this used to be (and should be) valid: profile.name.first_name given the schema below. Now, tsc raises an error because first_name isn't a property of an object.

openapi-generator version

4.2.3

Previous versions set type to any. Not sure which versions; 4.0.0-beta3 is known to have worked.

OpenAPI declaration file content or url

swagger: '2.0'
info:
  title: test
  version: v1
basePath: /api/v1
consumes:
  - application/json
produces:
  - application/json
paths:
  /users/profile:
    get:
      operationId: user_profile
      description: Get my profile
      parameters: []
      responses:
        '200':
          description: ''
          schema:
            $ref: '#/definitions/Profile'
definitions:
  Profile:
    type: object
    properties:
      name:
        title: Name
        type: object

Command line used for generation

Steps to reproduce

Related issues/PRs

Suggest a fix

Set type to any for typescript values set from an openapi spec object field.

Start with the typescript-fetch generator's schema type mapping and reproduce the issue using the YAML OpenAPI declaration in the report. Done means an unrestricted object, including one with additionalProperties: true, generates as any and a regression test covers the behavior.