Update get-rates-with-shipment-details.md

Author: sushithegreat

docs/get-rates-with-shipment-details.md

@@ -67,7 +67,7 @@ public class ShipEngineDemo {
                         )
                 ));
 
-        Map<String, String> result = shipengine.createLabelFromShipmentDetails(shipmentDetails);
+        Map<String, String> result = shipengine.getRatesWithShipmentDetails(shipmentDetails);
         System.out.println("result = " + result);
     }
 }
@@ -253,4 +253,4 @@ Exceptions
 ----------
 
 - This method will only throw an exception that is an instance/extension of **ShipEngineException** if there is a
-  problem if a problem occurs, such as a network error or an error response from the API.
+  problem if a problem occurs, such as a network error or an error response from the API.