jaxrs-spec: openapi.yaml file is empty

Created by: jmini

When generating a project with the jaxrs-spec generator (JavaJAXRSSpecServerCodegen class) a file src/main/openapi/openapi.yaml is created. This file is empty.

See the samples/server/petstore/jaxrs-spec sample (created with bin/jaxrs-spec-petstore-server.sh): openapi.yaml