Fixed the elevator time display and increased the elevator timer (#22510)

fixes https://github.com/Aurorastation/Aurora.3/issues/22409

The reason for the increased elevator timer was due to how rarely it
came up that the supplier time would be longer than the base 30 second
timer, so instead the two timers were combined to trial how a longer
timer would feel.

code/controllers/subsystems/cargo.dm

@@ -439,7 +439,7 @@ SUBSYSTEM_DEF(cargo)
 				new_shipment()
 
 			// Set the elevator movement time.
-			current_shipment.shuttle_time = get_pending_shipment_time()
+			current_shipment.shuttle_time = get_pending_shipment_time() + min_movetime
 			current_shipment.shuttle_fee = shipment_cost
 
 			if(current_shipment.shuttle_time < min_movetime)
@@ -453,7 +453,7 @@ SUBSYSTEM_DEF(cargo)
 			movetime = current_shipment.shuttle_time
 			//Launch it
 			shuttle.launch(src)
-			. = "The cargo elevator has been called and will arrive in approximately [shuttle.eta_seconds()] seconds."
+			. = "The cargo elevator has been called and will arrive in approximately [shuttle.launch_estimate(TRUE)] seconds."
 			current_shipment.shuttle_called_by = requester_name
 
 // Cancels the elevator. Can return a status message.