Give full path to feeds in findFeed

[relekang]

{ findFeed(url:"https://xkcd.com") { link } }

should give

{
  "data": {
    "findFeed": [
      {
        "link": "https://xkcd.com/atom.xml"
      },
      {
        "link": "https://xkcd.com/rss.xml"
      }
    ]
  }
}

currently it returns

{
  "data": {
    "findFeed": [
      {
        "link": "/atom.xml"
      },
      {
        "link": "/rss.xml"
      }
    ]
  }
}