fix(ask): fix url for "ask hn" stories
fix(ask): fix url for "ask hn" stories

Previously all "ask hn" stories were not opening in the browser
properly. This fixes the behavior by checking if the story doesn't have
an url. If it's the case, it should open the url on hn passing the story
id as a parameter (which will open the comments).

rafaelrinaldi/hn-cli