feat: button type

Author: mzahor

Src/Notion.Client/Models/Database/Properties/PropertyType.cs

@@ -71,5 +71,8 @@ public enum PropertyType
 
         [EnumMember(Value = "unique_id")]
         UniqueId,
+        
+        [EnumMember(Value = "button")]
+        Button,
     }
 }

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

@@ -77,5 +77,8 @@ public enum PropertyValueType
 
         [EnumMember(Value = "verification")]
         Verification,
+        
+        [EnumMember(Value = "button")]
+        Button,
     }
 }