Aspect ratio wrong when resize on an OrtographicLens

[vectorcharlie]

Hi! found that changing the lens to Ortographic, the resize function on QPanda3DWidget does not work, as the self.initial_size is declared as the self.size() value, which is a generic default from QT. Changing that to QSizeF(size.x, size.y) makes the Ortographic and Perspective lens work correctly