Fix some failure cases on FetchLinkCardService (#5347)
Fix some failure cases on FetchLinkCardService (#5347)

* If OEmbed response doesn't have a required property `type`, ignore it.
  e.g. `NoMethodError: undefined method 'type' for ...`
* If we failed to detect encoding, fallback to default behavior of Nokogiri.
  e.g. `KeyError: key not found: :encoding`
cobodo/mastodon,cobodo/mastodon,cobodo/mastodon,cobodo/mastodon