[BUG][Typescript-axios] Missing import with only additionalProperties object with array and ref

Created by: LiamMartens

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Have you provided a full/minimal spec to reproduce the issue?
Have you validated the input using an OpenAPI validator (example)?
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Description

When a response returns an object with only additionalProperties of type array with a ref the import is missing in the code generation (as seen in the gist). It does work correctly if the response was an object with additionalProperties of simply that ref for example.

openapi-generator version

4.2.3

OpenAPI declaration file content or url

Swagger JSON

Command line used for generation

Using NodeJS - yarn openapi-generator generate -c config.json --enable-post-process-file -i swagger.json -g typescript-axios -o ./src/openapi Our config.json is as follows

{
  "withSeparateModelsAndApi": true,
  "modelPackage": "models",
  "apiPackage": "api"
}

(this issue is only relevant if you have withSeparateModelsAndApi enabled)

Steps to reproduce

Simply generate using the provided swagger.json

Related issues/PRs

Suggest a fix

Need to investigate further