Fixed PyAccess after changing ICO size

[radarhere]

As with GifImagePlugin

Pillow/src/PIL/GifImagePlugin.py

Lines 325 to 333 in edcfe09

	self.pyaccess = None
	if "transparency" in self.info:
	self.im.putpalettealpha(self.info["transparency"], 0)
	self.im = self.im.convert("RGBA", Image.Dither.FLOYDSTEINBERG)
	self.mode = "RGBA"
	del self.info["transparency"]
	else:
	self.mode = "RGB"
	self.im = self.im.convert("RGB", Image.Dither.FLOYDSTEINBERG)

and PngImagePlugin

Pillow/src/PIL/PngImagePlugin.py

Lines 1004 to 1006 in edcfe09

	self.im = self._prev_im
	if self.pyaccess:
	self.pyaccess = None

after replacing self.im, self.pyaccess should be cleared.