**Update**

We discussed and decide this CLI should always only clean up pods created by Airflow.

<hr>

### Description

Currently command `kubernetes cleanup-pods` cleans up Pods that meet specific conditions in a given namespace.

Underlying code: https://github.com/apache/airflow/blob/2.0.1/airflow/cli/commands/kubernetes_command.py#L70

### Use case / motivation

The problem to me is: users may have other non-Airflow stuff running in this specific namespace, and they may want to have different strategy/logic for Pod cleaning-up for these non-Airflow pods.

We may want to have an additional boolean flag for this command, like `--only-airflow-pods`, so that users can decide if they only want to clean up Airflow-created Pods.

It should not be hard to identify Airflow-created pods, given the specific labels Airflow adds to the Pods it creates (https://github.com/apache/airflow/blob/2.0.1/airflow/kubernetes/pod_generator.py#L385)




tests/cli/commands/test_kubernetes_command.py
self, load_incluster_config, list_namespaced_pod, delete_pod
    ):
        pod1 = MagicMock()
        pod1.metadata.name = 'dummy2'
        pod1.status.phase = 'Failed'
        pod1.status.reason = None
        pod1.spec.restart_policy = 'Always'
        pods = MagicMock()
        pods.metadata._continue = None
        pods.items = [pod1]
        list_namespaced_pod.return_value = pods
        kubernetes_command.cleanup_pods(
            self.parser.parse_args(['kubernetes', 'cleanup-pods', '--namespace', 'awesome-namespace'])
        )
        list_namespaced_pod.assert_called_once_with(namespace='awesome-namespace', limit=500)
        delete_pod.assert_not_called()
        load_incluster_config.assert_called_once()
    @mock.patch('airflow.cli.commands.kubernetes_command._delete_pod')
    @mock.patch('kubernetes.client.CoreV1Api.list_namespaced_pod')
    @mock.patch('kubernetes.config.load_incluster_config')
    def test_cleanup_failed_pods_w_restart_policy_never(