Fixing NPE when fetching opeartion

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/push/notification/mgt/PushNotificationBasedOperationManager.java

@@ -46,7 +46,7 @@ public class PushNotificationBasedOperationManager implements OperationManager {
         Activity activity = this.operationManager.addOperation(operation, devices);
         for (DeviceIdentifier deviceId : devices) {
             try {
-                this.notificationProvider.execute(new NotificationContext(deviceId));
+                this.notificationProvider.execute(new NotificationContext(deviceId, operation));
             } catch (PushNotificationExecutionFailedException e) {
                 throw new OperationManagementException("Error occurred while sending push notification to device", e);
             }