Fix group attack for slime, zombie and zombiepig

mods/ENTITIES/mobs_mc/slime+magma_cube.lua

@@ -58,7 +58,7 @@ end
 local slime_big = {
 	type = "monster",
 	pathfinding = 1,
-	group_attack = true,
+	group_attack = { "mobs_mc:slime_big", "mobs_mc:slime_small", "mobs_mc:slime_tiny" },
 	hp_min = 16,
 	hp_max = 16,
 	collisionbox = {-1.02, -0.01, -1.02, 1.02, 2.03, 1.02},

mods/ENTITIES/mobs_mc/zombie.lua

@@ -65,8 +65,8 @@ local zombie = {
 	fear_height = 4,
 	pathfinding = 1,
 	jump = true,
-	--jump_height = 3,
-	group_attack = true,
+	jump_height = 4,
+	group_attack = { "mobs_mc:zombie", "mobs_mc:baby_zombie", "mobs_mc:husk", "mobs_mc:baby_husk" },
 	drops = drops_zombie,
 	animation = {
 		speed_normal = 25,		speed_run = 50,
@@ -75,7 +75,6 @@ local zombie = {
 		run_start = 0,		run_end = 40,
 	},
 	lava_damage = 4,
-	-- TODO: Burn mob only when in direct sunlight
 	sunlight_damage = 2,
 	view_range = 16,
 	attack_type = "dogfight",

mods/ENTITIES/mobs_mc/zombiepig.lua

@@ -18,7 +18,7 @@ local pigman = {
 	hp_max = 20,
 	armor = 90,
 	attack_type = "dogfight",
-	group_attack = true,
+	group_attack = { "mobs_mc:pigman", "mobs_mc:baby_pigman" },
 	damage = 9,
 	reach = 2,
 	collisionbox = {-0.3, -0.01, -0.3, 0.3, 1.94, 0.3},