Don't reuse http messages

Wabbajack.Common/Http/Client.cs

@@ -53,10 +53,21 @@ namespace Wabbajack.Common.Http
                 retries++;
                 Utils.Log($"Http Connect error to {msg.RequestUri} retry {retries}");
                 await Task.Delay(100 * retries);
+                msg = CloneMessage(msg);
                 goto TOP;
 
             }
 
         }
+
+        private HttpRequestMessage CloneMessage(HttpRequestMessage msg)
+        {
+            var new_message = new HttpRequestMessage(msg.Method, msg.RequestUri);
+            foreach (var header in msg.Headers)
+                new_message.Headers.Add(header.Key, header.Value);
+            new_message.Content = msg.Content;
+            return new_message;
+
+        }
     }
 }

Wabbajack.Test/HttpClientTests.cs

@@ -0,0 +1,18 @@
+using System.Net.Http;
+using System.Threading.Tasks;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace Wabbajack.Test
+{
+    [TestClass]
+    public class HttpClientTests
+    {
+        [TestMethod]
+        public async Task DoesntReuseHttpMessages()
+        {
+            var client = new Common.Http.Client();
+            // If we reuse the HTTP message this will throw a invalid operation exception
+            await Assert.ThrowsExceptionAsync<HttpRequestException>(async () => await client.GetAsync("http://blerg.blaz.bloz.buz"));
+        }
+    }
+}