fix nullref in scale monitor (#97)

src/DurableTask.Netherite/OrchestrationService/NetheriteOrchestrationService.cs

@@ -175,7 +175,8 @@ namespace DurableTask.Netherite
                     this.Settings.ResolvedTransportConnectionString, 
                     this.Settings.LoadInformationAzureTableName, 
                     this.Settings.HubName,
-                    this.TraceHelper.TraceScaleRecommendation);
+                    this.TraceHelper.TraceScaleRecommendation,
+                    this.TraceHelper.Logger);
                 return true;
             }
             else

src/DurableTask.Netherite/Scaling/ScalingMonitor.cs

@@ -50,13 +50,15 @@ namespace DurableTask.Netherite.Scaling
             string eventHubsConnectionString, 
             string partitionLoadTableName, 
             string taskHubName,
-            Action<string, int, string> recommendationTracer)
+            Action<string, int, string> recommendationTracer,
+            ILogger logger)
         {
             this.storageConnectionString = storageConnectionString;
             this.eventHubsConnectionString = eventHubsConnectionString;
             this.partitionLoadTableName = partitionLoadTableName;
             this.taskHubName = taskHubName;
             this.recommendationTracer = recommendationTracer;
+            this.Logger = logger;
 
             TransportConnectionString.Parse(eventHubsConnectionString, out _, out this.configuredTransport);