doc(MockSocket): update mock socket sample (#7704)

Author: ArgoZhang

src/BootstrapBlazor.Server/Services/MockDisconnectService.cs

@@ -1,4 +1,4 @@
-// Licensed to the .NET Foundation under one or more agreements.
+// Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the Apache 2.0 License
 // See the LICENSE file in the project root for more information.
 // Maintainer: Argo Zhang(argo@live.ca) Website: https://www.blazor.zone
@@ -54,6 +54,7 @@ private async Task OnDataHandlerAsync(TcpClient client, CancellationToken stoppi
             catch (OperationCanceledException) { break; }
             catch (IOException) { break; }
             catch (SocketException) { break; }
+            catch (ObjectDisposedException) { break; }
             catch (Exception ex)
             {
                 logger.LogError(ex, "MockDisconnectServerService encountered an error while sending data.");