feat(tiered_pricing): 🔵 refactoring magic numbers

Author: oflorez1381

exercises/tiered_pricing/solutions/oflorez/src/test/java/tv/codely/checkout/TieredPricingShould.java

@@ -26,8 +26,8 @@ void calculate_total_value_for_second_pricing_range() {
     @Test
     void calculate_total_value_for_third_pricing_range() {
         var pricing = new TieredPricing();
-        var subscription = retrieveSubscriptionGivenRange(11,25);
-        assertEquals(calculateTotalPriceExpected(219, subscription), pricing.calculateTotalPrice(subscription));
+        var subscription = retrieveSubscriptionGivenRange(THIRD_RANGE_LOWER_LIMIT,THIRD_RANGE_UPPER_LIMIT);
+        assertEquals(calculateTotalPriceExpected(THIRD_RANGE_UNIT_PRICE, subscription), pricing.calculateTotalPrice(subscription));
     }
 
     private int retrieveSubscriptionGivenRange(int lowerLimit, int upperLimit) {