Fixing SystemLogger formattedMessage bug (#10555)

Author: RohitRanjanMS

src/WebJobs.Script.WebHost/Diagnostics/SystemLogger.cs

@@ -152,7 +152,6 @@ public void Log<TState>(LogLevel logLevel, EventId eventId, TState state, Except
             // Apply standard event properties.
             // Note: we must be sure to default any null values to empty string
             // otherwise the ETW event will fail to be persisted (silently).
-            string summary = formattedMessage ?? string.Empty;
             string eventName = !string.IsNullOrEmpty(eventId.Name) ? eventId.Name : stateEventName ?? string.Empty;
             eventName = isDiagnosticEvent ? $"DiagnosticEvent-{diagnosticEventErrorCode}" : eventName;
 
@@ -178,7 +177,8 @@ public void Log<TState>(LogLevel logLevel, EventId eventId, TState state, Except
                 formattedMessage = Sanitizer.Sanitize(formattedMessage);
                 innerExceptionMessage = innerExceptionMessage ?? string.Empty;
             }
-            _eventGenerator.LogFunctionTraceEvent(logLevel, subscriptionId, appName, functionName, eventName, source, details, summary, innerExceptionType, innerExceptionMessage, invocationId, _hostInstanceId, activityId, runtimeSiteName, slotName, DateTime.UtcNow);
+
+            _eventGenerator.LogFunctionTraceEvent(logLevel, subscriptionId, appName, functionName, eventName, source, details, formattedMessage, innerExceptionType, innerExceptionMessage, invocationId, _hostInstanceId, activityId, runtimeSiteName, slotName, DateTime.UtcNow);
         }
     }
 }