set completed_session not print nu llparameter

EVCB_OCPP.WSServer/Service/BusinessService/OuterBusinessService.cs

@@ -346,7 +346,7 @@ namespace EVCB_OCPP.WSServer.Service.BusinessService
 
             };
 
-            logger.LogDebug("completed_session " + JsonConvert.SerializeObject(request));
+            logger.LogDebug("completed_session " + JsonConvert.SerializeObject(request, GlobalConfig.JSONSERIALIZER_FORMAT));
             var response = await httpClient.Post(
                 signMaterial.APIUrl + "completed_session", 
                 new Dictionary<string, string>()