add explicit JsonIgnore attribute to IncludeTime property in Date class

Author: KoditkarVedant

Src/Notion.Client/Models/PropertyValue/DatePropertyValue.cs

@@ -48,6 +48,7 @@ public class Date
         /// <summary>
         ///     Whether to include time
         /// </summary>
+        [JsonIgnore]
         public bool IncludeTime { get; set; } = true;
     }
 }