Done Add Mega Metagross' Shiny sprite

[Renegade1408]

I've noticed that Mega Metagross' shiny sprite is the same as the regular one, but on the XY sprite project list he has a completed shiny sprite, idk if there's a reason it hasn't been added or if it was just forgotten, but could you add the shiny sprite?
I've not noticed this problem with any other mega sprites or any sprites in general (other than Magearna, who doesn't have a shiny in its regular form)