Punycode URI normalization (#2370)

* Fix #2119 - Whenever about to send a HTTP request, normalize the URI

* Add test for IDN request in FetchLinkCardService

* Perform IDN normalization on domains before they are stored in the DB

app/services/fetch_remote_account_service.rb

@@ -21,7 +21,7 @@ class FetchRemoteAccountService < BaseService
 
     email = xml.at_xpath('//xmlns:author/xmlns:email').try(:content)
     if email.nil?
-      url_parts = Addressable::URI.parse(url)
+      url_parts = Addressable::URI.parse(url).normalize
       username  = xml.at_xpath('//xmlns:author/xmlns:name').try(:content)
       domain    = url_parts.host
     else