IgnoreConfig IsEmty property is ignored during yaml de/serialization

Author: mirecad

src/GitVersionCore/Model/Configuration/IgnoreConfig.cs

@@ -19,6 +19,7 @@ public IgnoreConfig()
         [YamlMember(Alias = "sha")]
         public IEnumerable<string> ShAs { get; set; }
 
+        [YamlIgnore]
         public virtual bool IsEmpty => Before == null
                                        && (ShAs == null || ShAs.Any() == false);