CustomBufferedStream were not disposed

[StephaneGraziano]

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• Build is okay - I made sure that this change is building successfully.
• No Bugs - I made sure that this change is working properly as expected. It doesn't have any bugs that you are aware of.
• Branching - If this is not a hotfix, I am making this request against the master branch

The previous code :

// 1st clientStream
var clientStream = new CustomBufferedStream(clientConnection.GetStream(), BufferPool, BufferSize);
sslStream = new SslStream(clientStream, true); //true => do not dispose 1st ClientStream
// 2nd clientStream
clientStream = new CustomBufferedStream(sslStream, BufferPool, BufferSize);

...

sslStream?.Dispose(); // dispose sslStream but not 1st ClientStream
clientStream.Dispose(); // dispose 2nd ClientStream + sslStream (already disposed)
// here 1st clientStream is not disposed

The workaround is to handle the dispose of 1st clientStream inside SslStream.

sslStream = new SslStream(clientStream, false);