add sort test for Fixed8

neo.UnitTests/UT_Fixed8.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Linq;
 using FluentAssertions;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
 
@@ -46,5 +47,26 @@ public void Can_multiply_without_overflow()
             Fixed8 actual = af * bf;
             ((decimal)actual).Should().Be(expected);
         }
+
+        [TestMethod]
+        public void Sort()
+        {
+            Fixed8[] numbers = new[]
+            {
+                Fixed8.FromDecimal(5),
+                Fixed8.FromDecimal(7),
+                Fixed8.FromDecimal(2),
+                Fixed8.FromDecimal(4),
+                Fixed8.FromDecimal(1),
+                Fixed8.FromDecimal(8),
+                Fixed8.FromDecimal(9),
+                Fixed8.FromDecimal(0),
+                Fixed8.FromDecimal(3),
+                Fixed8.FromDecimal(6)
+            };
+            numbers = numbers.OrderBy(p => p).ToArray();
+            for (int i = 0; i < numbers.Length; i++)
+                numbers[i].Should().Be(Fixed8.FromDecimal(i));
+        }
     }
 }