Initial Window Size is not correct

[mgradwohl]

On some machines, this code is correct, on others it is not.

       // TODO doesn't work at all monitor DPIs http://microsoft.github.io/Win2D/WinUI3/html/DPI.htm
        const int wndWidth = theCanvas().ConvertDipsToPixels(bestcanvassize + 240, CanvasDpiRounding::Ceiling);
		const int wndHeight = theCanvas().ConvertDipsToPixels(bestcanvassize + 40, CanvasDpiRounding::Ceiling);
        
        //const int wndWidth = bestcanvassize + 240;
        //const int wndHeight = bestcanvassize + 40;
		appWnd.ResizeClient(Windows::Graphics::SizeInt32{ wndWidth, wndHeight });