Update demo

Src/Asp.Net/MySqlTest/Demo/Demo1_Queryable.cs

@@ -83,6 +83,7 @@ namespace OrmTest
             var getByFuns2 = db.Queryable<Order>().GroupBy(it => it.Name).Select(it => SqlFunc.AggregateDistinctCount(it.Price)).ToList();
             var dp = DateTime.Now;
             var test05 = db.Queryable<Order>().Where(it => it.CreateTime.Month == dp.Month).ToList();
+            var fromatList = db.Queryable<Order>().Select(it => it.CreateTime.ToString("%Y-%m")).ToList();
             Console.WriteLine("#### Examples End ####");
         }