Reset spiderling walk instructions on Destroy. (#19171)

Author: warriorstar-orion

code/game/objects/effects/spiders.dm

@@ -111,6 +111,8 @@
 
 /obj/structure/spider/spiderling/Destroy()
 	STOP_PROCESSING(SSobj, src)
+	// Release possible ref if a walk is still being processed
+	walk_to(src, 0)
 	entry_vent = null
 	if(amount_grown < 100)
 		new /obj/effect/decal/cleanable/spiderling_remains(get_turf(src))