13.0.0: --route-types option is ignored

# Summary

It appears that swagger-typescript-api started ignoring the "--route-types" option from version 13.0.0.

# Version

- swagger-typescript-api: 13.0.0
- Node.js: 18.16.0

# Reproduce

I created a sample project to reproduce this behavior.

https://codesandbox.io/p/sandbox/sleepy-golick-5zt4wz?file=%2Fpackage.json%3A25%2C32

1. Run `npx sta -p oas.yaml --no-client --route-types` in terminal.
2. The generated ts file `Api.ts` has no routes typings.

It seems internal variable `config.generateRouteTypes` cannot be set to true.