[BUG] [Typescript-Axios] ModuleParseError: Module parse failed: The keyword 'protected' is reserved

Bug Report Checklist

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

When creating a TypeScript-axios client for the API.protected and public reserved words cannot be compiled when used with Storybook.

openapi-generator version

6.4.0

OpenAPI declaration file content or url

Generation Details

Steps to reproduce

Just generate source code for typescript-axios.

ModuleParseError: Module parse failed: The keyword 'protected' is reserved (80:79)
File was processed with these loaders:
 * ./node_modules/babel-loader/lib/index.js
You may need an additional loader to handle the result of these loaders.
|  * @class BaseAPI
|  */
> export var BaseAPI = /*#__PURE__*/_createClass(function BaseAPI(configuration, protected basePath = BASE_PATH, protected axios = globalAxios) {
|   _classCallCheck(this, BaseAPI);
|   this.configuration = void 0;

Related issues/PRs

Suggest a fix

Current code:

export class BaseAPI {
    protected configuration: Configuration | undefined;
    constructor(configuration?: Configuration, protected basePath: string = BASE_PATH, protected axios: AxiosInstance = globalAxios) {
        if (configuration) {
            this.configuration = configuration;
            this.basePath = configuration.basePath || this.basePath;
        }
    }
};

Corrected code:

export class BaseAPI {
    protected configuration: Configuration | undefined;
    protected basePath: string | undefined;
    protected axios: AxiosInstance | undefined;
    
    constructor(configuration?: Configuration, basePath: string = BASE_PATH, axios: AxiosInstance = globalAxios) {
        if (configuration) {
            this.configuration = configuration;
            this.basePath = configuration.basePath || this.basePath;
        }
    }
};

Start by generating a TypeScript-Axios client from the reported API declaration and reproduce the Storybook/Babel ModuleParseError. Inspect the generated BaseAPI constructor and compare it with the corrected code shown in the issue, then verify that the generated client compiles without reserved-word parse errors.