title: Generate Swagger documentation as JSON/YAML in NestJS
body: <p>I've followed the <a href="https://docs.nestjs.com/recipes/swagger" rel="noreferrer">instructions to create a Swagger documentation</a>, and my documentation is now available using Swagger UI. I'd like to also generate the documentation as JSON or YAML so it's easy to import in e.g. Postman, but I can't find any suitable methods in the <code>SwaggerModule</code>, nor does the Swagger UI have any export button. </p>