[MIRROR] Clears unused research var (#12685)

Co-authored-by: Cameron Lennox <killer65311@gmail.com>

code/game/objects/items/weapons/material/kitchen.dm

@@ -9,7 +9,6 @@
 	pickup_sound = 'sound/items/pickup/knife.ogg'
 	w_class = ITEMSIZE_TINY
 	thrown_force_divisor = 1
-	origin_tech = list(TECH_MATERIAL = 1)
 	attack_verb = list("attacked", "stabbed", "poked")
 	sharp = TRUE
 	edge = TRUE

code/game/objects/items/weapons/material/knives.dm

@@ -72,7 +72,6 @@
 	edge = TRUE
 	force_divisor = 0.15 // 9 when wielded with hardness 60 (steel)
 	matter = list(MAT_STEEL = 12000)
-	origin_tech = list(TECH_MATERIAL = 1)
 	attack_verb = list("slashed", "stabbed", "sliced", "torn", "ripped", "diced", "cut")
 	drop_sound = 'sound/items/drop/knife.ogg'
 

code/game/objects/items/weapons/material/misc.dm

@@ -18,7 +18,6 @@
 	w_class = ITEMSIZE_SMALL
 	sharp = TRUE
 	edge = TRUE
-	origin_tech = list(TECH_MATERIAL = 2, TECH_COMBAT = 1)
 	attack_verb = list("chopped", "torn", "cut")
 	applies_material_colour = 0
 	drop_sound = 'sound/items/drop/axe.ogg'
@@ -121,7 +120,6 @@
 	default_material = MAT_LEATHER
 	slot_flags = SLOT_BELT
 	w_class = ITEMSIZE_NORMAL
-	origin_tech = list(TECH_COMBAT = 2)
 	attack_verb = list("flogged", "whipped", "lashed", "disciplined")
 	force_divisor = 0.15
 	thrown_force_divisor = 0.25
@@ -228,7 +226,6 @@
 	icon = 'icons/obj/weapons_vr.dmi'
 	icon_state = "stone_wood_axe"
 	default_material = MAT_FLINT
-	origin_tech = list()
 	applies_material_colour = FALSE
 
 /obj/item/material/knife/machete/hatchet/stone/bone

code/game/objects/items/weapons/material/twohanded.dm

@@ -139,7 +139,6 @@
 	name = "scythe"
 	desc = "A sharp and curved blade on a long fibremetal handle, this tool makes it easy to reap what you sow."
 	force_divisor = 0.65
-	origin_tech = list(TECH_MATERIAL = 2, TECH_COMBAT = 2)
 	attack_verb = list("chopped", "sliced", "cut", "reaped")
 
 //spears, bay edition