update ulong to long?

Author: DeepakRajendranMsft

src/ResourceManager/Network/Commands.Network/Models/PSTunnelConnectionHealth.cs

@@ -22,9 +22,9 @@ public class PSTunnelConnectionHealth
 
         public string ConnectionStatus { get; set; }
 
-        public ulong IngressBytesTransferred { get; set; }
+        public long? IngressBytesTransferred { get; set; }
 
-        public ulong EgressBytesTransferred { get; set; }
+        public long? EgressBytesTransferred { get; set; }
 
         public string LastConnectionEstablishedUtcTime { get; set; }
     }