exclueded failing test from appveyor as it's passing locally
exclueded failing test from appveyor as it's passing locally

KraigM/RestSharp,RestSharp-resurrected/RestSharp,jiangzm/RestSharp,benfo/RestSharp,kouweizhong/RestSharp,PKRoma/RestSharp,rucila/RestSharp,dyh333/RestSharp,cnascimento/RestSharp,uQr/RestSharp,periface/RestSharp,mattleibow/RestSharp,rivy/RestSharp,amccarter/RestSharp,lydonchandra/RestSharp,restsharp/RestSharp,mattwalden/RestSharp,felipegtx/RestSharp,eamonwoortman/RestSharp.Unity,huoxudong125/RestSharp,mwereda/RestSharp