Typesave serialization of openapi spec

[raddatzk]

I was trying to integrate spring cloud config into our project and used the openAPI() bean for testing.

@Bean
@RefreshScope
public OpenAPI openAPI() {
    return new OpenAPI()
        .info(new Info()
                    .title("title)
                    .description("description")
                    .version("1.0.0")
         );
}

By default spring uses the proxy method TARGET_CLASS to generate a refreshScope bean which adds multiple properties which will be serialized by the objectMapper. Serialization of those properties results in an infinite loop and thus in a StackOverflowError.

With these changes the openAPI object will be serialized for the OpenAPI class, ignoring the properties added by spring.

[bnasslahsen]

thank you @kevinraddatz for your contribution;