add dispose for reader in monitor event. to prevent memory leak.

DataCenter_Windows/WindowsDataCenter/CardReaderService/CardReaderService.cs

@@ -142,7 +142,7 @@ namespace CardReaderService
                 {
                     _logger.Trace("Reader failed to connect, error: " + Enum.GetName(typeof(SCardError), err));
                 }
-
+                reader.Dispose();
             }
         }