Reduce the Hanzo arrow size

[Agranite-1626]

It was specified by the developers themselves.

Hanzo's Arrows' Hitboxes needs nerf in Size

Despite the memes to the contrary, Hanzo’s arrows aren’t actually all that big. They are tied for the smallest projectile in the game with a couple other things, sich as Genji’s shurikens. For example, Mercy and D.Va pilot weapons are 2.5x bigger than Hanzo arrows.

If you weren’t aware, the hitbox of Hanzo’s arrow is a ball located at the tail end of the arrow.