Hello,,

The [new Celery 5.0](https://docs.celeryproject.org/en/stable/whatsnew-5.0.html) has been released and we may consider migrating to this version. I don't know if it has to happen now, if we should wait for version 5.1 or do it now. I am creating this ticket to track this version.

To process this issue, we should consider the consequences of this update, update the CLI calls, update API calls, and test these versions thoroughly.

@auvipy Can you tell a little more about this release? Is this release stable enough to update our project to these versions?  What consequences could this update have?

tests/executors/test_celery_executor.py
raise Exception()
    def task_id(self):
        return "task_id"
@contextlib.contextmanager
def _prepare_app(broker_url=None, execute=None):
    broker_url = broker_url or conf.get('celery', 'BROKER_URL')
    execute = execute or celery_executor.execute_command.__wrapped__
    test_config = dict(celery_executor.celery_configuration)
    test_config.update({'broker_url': broker_url})
    test_app = Celery(broker_url, config_source=test_config)
    test_execute = test_app.task(execute)
    patch_app = mock.patch('airflow.executors.celery_executor.app', test_app)
    patch_execute = mock.patch('airflow.executors.celery_executor.execute_command', test_execute)
    backend = test_app.backend
    if hasattr(backend, 'ResultSession'):
        
        
        
        
        
        session = backend.ResultSession()
        session.close()
    with patch_app, patch_execute:
        try:
            yield test_app
        finally:
            
            set_event_loop(None)
class TestCeleryExecutor(unittest.TestCase):