Fix error in rsync task update

Here is the error From FreeNAS 11.3 INTERNAL

    def test_10_Disable_rsync_task(rsynctask_dict):
        id = rsynctask_dict['id']
        results = PUT(f'/rsynctask/id/{id}/', {'enabled': False})
>       assert results.status_code == 200, results.text
E       AssertionError: {
E          "datastore_update.job": [
E           {
E            "message": "job field not recognized",
E            "errno": 22
E           }
E          ]
E         }
E       assert 422 == 200
E         -422
E         +200

https://builds.ixsystems.com/view/QA%20Tests/view/All/job/FreeNAS%20-%2011.3%20-%20Internal%20(API%20Tests)/lastCompletedBuild/testReport/api2/rsync/Run_Tests___API_2_0___test_10_Disable_rsync_task/ 

it is also seen in FreeNAS - Master - Incremental Build https://builds.ixsystems.com/view/QA%20Tests/view/All/job/FreeNAS%20-%20Master%20-%20Incremental%20API%20Tests/96/testReport/junit/api2/rsync/Run_Tests___API_2_0___test_10_Disable_rsync_task/