Check for disconnection between handling messages

Without this, it is possible for clients to get the remainder of their
messages handled in a packet.

Co-Authored-By: js6pak <me@6pak.dev>

src/Impostor.Server/Net/Hazel/HazelConnection.cs

@@ -69,6 +69,11 @@ namespace Impostor.Server.Net.Hazel
                 {
                     await Client.HandleMessageAsync(message, e.Type);
                 }
+
+                if (!IsConnected)
+                {
+                    break;
+                }
             }
         }
     }