Revert "dispose of pixelbuffer"

This reverts commit ff89176.

src/Consolonia.Core/Infrastructure/ConsoleWindow.cs

@@ -334,7 +334,6 @@ private void OnConsoleOnResized()
                     // dispatch to the UI thread 
                     Dispatcher.UIThread.Post(() =>
                     {
-                        (PixelBuffer as IDisposable)?.Dispose();
                         PixelBuffer = new PixelBuffer(Console.Size);
                         var size = new Size(Console.Size.Width, Console.Size.Height);
                         Resized!(size, WindowResizeReason.Unspecified);