[browser][websocket] Canceling token source before connect should throw `OperationCanceledException`

[kjpou1]

The WebSocketClient should throw an OperationCanceledException instead of trying to connect and then cancelling.

            using (var clientSocket = new ClientWebSocket())
            {
                var cts = new CancellationTokenSource();
                cts.Cancel();
                Task t = clientSocket.ConnectAsync(new Uri("ws://" + Guid.NewGuid().ToString("N")), cts.Token);
            }

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Details

Issue Details

Description:	The WebSocketClient should throw an OperationCanceledException instead of trying to connect and then cancelling. using (var clientSocket = new ClientWebSocket()) { var cts = new CancellationTokenSource(); cts.Cancel(); Task t = clientSocket.ConnectAsync(new Uri("ws://" + Guid.NewGuid().ToString("N")), cts.Token); } }
Author:	kjpou1
Assignees:	kjpou1
Labels:	arch-wasm, area-System.Net.Sockets
Milestone:	-