Merge pull request #40 from FromDoppler/DD-1248-change-type

[DD-1248] change type

GreenArrow.Engine/Model/Events/DeliveryAttempt.cs

@@ -123,7 +123,7 @@ public enum StatusEnum
         /// <summary>
         /// Internal use Studio feature that’s not yet documented.
         /// </summary>
-        public int Sendsliceid { get; init; }
+        public string Sendsliceid { get; init; }
 
         /// <summary>
         /// Blank if the delivery attempt took place using an SMTP Relay Server or the default Throttling Rule.
@@ -152,7 +152,7 @@ public enum StatusEnum
         /// Folded headers will simply contain the folding newlines/whitespace.
         /// As a header may be included in an email multiple times, the value of the JSON object is an array of strings.
         /// </summary>
-        public object Headers { get; init; }
+        public Dictionary<string, List<string>> Headers { get; init; }
 
         /// <summary>
         /// The size of the message (in bytes), if loaded from storage.