Merge pull request #1742 from aspnet/release/2.1

Adding File Header (#1741)

test/Microsoft.AspNetCore.SignalR.Tests.Utils/WebSocketsSupportedConditionAttribute.cs

@@ -1,4 +1,7 @@
-using System;
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System;
 using System.Collections.Generic;
 using System.Runtime.InteropServices;
 using System.Text;
@@ -36,4 +39,4 @@ namespace Microsoft.AspNetCore.SignalR.Tests
 
         public string SkipReason => "No WebSockets Client for this platform";
     }
-}
+}