title: HttpClient SendAsync is not sending cookies
body: <pre><code>var Url = &quot;https://myhost.com/api&quot;;
  var UrlEncodedContent = GetContent();
  var CookieContainer = new CookieContainer();
  using(var clientHandler = new HttpClientHandler() { CookieContainer = CookieContainer })
  {
      Uri Endpoint = new Uri(&quot;https://myhost.com&quot;);
      CookieContainer.Add(Endpoint, new Cookie(&quot;mycookie&quot;, &quot;abc&quot;));
  
      var Request = new HttpRequestMessage(HttpMethod.Post, Url) { Content = UrlEncodedContent };
  
      var Response = MyHttpClient.SendAsync(Request); 
  } 
  </code></pre>
  <p>The client is not sending the cookies. I have confirmed this by looking at the request in Fiddler.
  As far as i can tell this should work correctly.</p>