Fix one bug of the macOS API `SDScaledImageForKey`, which does not modify the bitmapImageRep's size when scale is not equal to 1
Fix one bug of the macOS API `SDScaledImageForKey`, which does not modify the bitmapImageRep's size when scale is not equal to 1

dreampiggy/SDWebImage,rs/SDWebImage,awkward/SDWebImage,dreampiggy/SDWebImage,awkward/SDWebImage,tualatrix/SDWebImage,dreampiggy/SDWebImage,zhang-yawei/SDWebImage,awkward/SDWebImage