Fix Ferrum::Network::Response#loaded? for redirect response (#338)

Co-authored-by: Diana Carrier <[email protected]>

Author: francisbeaudoin

lib/ferrum/network.rb

@@ -362,6 +362,7 @@ def subscribe_request_will_be_sent
         if params["redirectResponse"]
           previous_exchange = select(request.id)[-2]
           response = Network::Response.new(@page, params)
+          response.loaded = true
           previous_exchange.response = response
         end