public void ConfigureServices(IServiceCollection services)
{
     services.AddSwaggerGen(c =>
            {
                c.SwaggerDoc("v1", new OpenApiInfo { Title = "Document Generation API", Version = "v1" });
                // Tell Swagger where to find operation ID. 
                // In this example, use the controller action name. 
                c.CustomOperationIds(d => (d.ActionDescriptor as ControllerActionDescriptor)?.ActionName);
            });
}