[Rb] Improves ruby bridge for url parsing rfc suite

Author: codeZeilen

rosetta-test-rb/url_parsing.rb

@@ -21,7 +21,7 @@
   end
 
   placeholder "url-authority" do |_env, uri|
-    authority = uri.host
+    authority = uri.host || ""
     authority = "#{uri.userinfo}@#{authority}" if uri.userinfo
     authority = "#{authority}:#{uri.port}" if uri.port
     authority