Destroying clipping region is since 106b850593
("Fix wxCairoContext::ResetClip() for wxGTK", 2022-10-28) fully handled in
parent wxGCDCImpl::DestroyClippingRegion() calling wxCairoContext::ResetClip()
(including re-establishing clip for paint update area) so there is no need
to implement overriding method in wxPaintDCImpl.
Closes#23046.