[BUG] [graphql-nodejs-express-server] generates improper model for arrays

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

My spec has an array in it, when I run the generator, the model for the array is an empty type.

openapi-generator version

CLI version 4.2.3

OpenAPI declaration file content or url

openapi: '3.0.0'
info:
  title: My API
  description: This is a test
  version: 0.1.1

paths:
  /someArray:
    get:
      summary: Returns an array
      responses:
        200:
          description: OK
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/SomeArray'
components:
  schema:
    SomeArray:
      type: array
      items:
          type: integer

Command line used for generation

java -jar codegen-cli.jar generate -i test.yml -g graphql-nodejs-express-server -o /out/graphql-nodejs-express-server --generate-alias-as-model

Steps to reproduce

1. Copy/paste the yaml above into a test.yml
2. Call the command above via command line

Related issues/PRs

NA

Suggest a fix

This is a tough one. OpenAPI doesn't provide a name element for array types, but GraphQL requires that each property be named (sensibly). Maybe the generator can use the type name?
Actual

type SomeArray {
}

input SomeArrayInput {
}

Expected

type SomeArray {
  someArray: [Int]
}

input SomeArrayInput {
    someArray: [Int]
}

Reproduce the issue with the supplied test.yml and the graphql-nodejs-express-server generation command. Start by inspecting that generator's model templates or entry points to see how array schemas are represented. Done means SomeArray and SomeArrayInput contain the expected [Int] field rather than empty types, with a regression test covering the example.