remove redundant loop in ruin placement (#29676)

code/datums/mapping/ruin_placer.dm

@@ -64,13 +64,12 @@
 				bottom_left.y_pos -= padding
 				top_right.x_pos += padding
 				top_right.y_pos += padding
-				var/list/affected_turfs = block(bottom_left.x_pos, bottom_left.y_pos, z_level, top_right.x_pos, top_right.y_pos, z_level)
 
 				// One sanity check just in case
 				if(!ruin.fits_in_map_bounds(central_turf, centered = TRUE))
 					valid = FALSE
 
-				for(var/turf/check in affected_turfs)
+				for(var/turf/check in block(bottom_left.x_pos, bottom_left.y_pos, z_level, top_right.x_pos, top_right.y_pos, z_level))
 					var/area/new_area = get_area(check)
 					if(!(istype(new_area, area_whitelist)) || check.flags & NO_RUINS)
 						valid = FALSE
@@ -79,14 +78,6 @@
 				if(!valid)
 					continue
 
-				for(var/turf/T in affected_turfs)
-					for(var/obj/structure/spawner/nest in T)
-						qdel(nest)
-					for(var/mob/living/simple_animal/monster in T)
-						qdel(monster)
-					for(var/obj/structure/flora/ash/plant in T)
-						qdel(plant)
-
 				var/loaded = ruin.load(central_turf, centered = TRUE)
 				if(!loaded)
 					stack_trace("ruin [ruin.suffix] failed to load at [COORD(central_turf)] after valid bounds check")