[REQ][TYPESCRIPT-AXIOS] Add option to not stringify JSON data in axios-typescript generator

Problem Statement

The generator always serializes objects to string with JSON.stringify. This is not always wanted, which is why it should configurable. In my case I wanted to write an AxiosTransformer, which transforms JavaScript Date types to the correct format. In order to do this now, I have to JSON.parse the data and then check it.

Here is the line in question:
https://github.com/OpenAPITools/openapi-generator/blob/ce49fe587fe6ab4dcc2275590f49fb0b09777710/modules/openapi-generator/src/main/resources/typescript-axios/apiInner.mustache#L199

Prefered Solution

Add new option to the config, when generating the client:

{
  "stringifyRequestData": false
}

Start with modules/openapi-generator/src/main/resources/typescript-axios/apiInner.mustache at the linked JSON.stringify call, then trace how typescript-axios generator options reach that template. Done means the new stringifyRequestData option can disable serialization while preserving the existing default behavior; verify the generated client output for both settings.