Fix edge case lua error in human behaviours

Author: garethyr

Base.rte/AI/HumanBehaviors.lua

@@ -2128,6 +2128,7 @@ function HumanBehaviors.GetProjectileData(Owner)
 		PrjDat.vel = 100;
 		PrjDat.rng = math.huge;
 		PrjDat.pen = math.huge;
+		PrjData.blast = 0;
 	else
 		-- find muzzle velocity
 		PrjDat.vel = Weapon:GetAIFireVel();