refactor: update type comparison in ValueObjectTests to use GetType method

Author: kamilbaczek

Chapter-4-applying-tactical-domain-driven-design/Fitnet.Common/Fitnet.Common.Core.UnitTests/ValueObjectTests.cs

@@ -61,7 +61,7 @@ internal void Given_two_different_type_objects_When_values_are_the_same_Then_sho
         var secondObject = new AnotherTypeFakeValueObject();
 
         // Act & Assert
-        // firstObject.ShouldNotBe(secondObject);
+        firstObject.GetType().ShouldNotBe(secondObject.GetType());
         firstObject.Equals(secondObject).ShouldBeFalse();
         (firstObject == secondObject).ShouldBeFalse();
         (firstObject != secondObject).ShouldBeTrue();