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/controllers/authorize_follow_controller.rb

@@ -6,7 +6,7 @@ class AuthorizeFollowController < ApplicationController
   before_action :authenticate_user!
 
   def new
-    uri = Addressable::URI.parse(acct_param)
+    uri = Addressable::URI.parse(acct_param).normalize
 
     if uri.path && %w(http https).include?(uri.scheme)
       set_account_from_url