**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)




airflow/cli/cli_parser.py
ActionCommand(
        name='widgets',
        help='Get information about registered connection form widgets',
        func=lazy_load_command('airflow.cli.commands.provider_command.connection_form_widget_list'),
        args=(
            ARG_OUTPUT,
            ARG_VERBOSE,
        ),
    ),
    ActionCommand(
        name='hooks',
        help='List registered provider hooks',
        func=lazy_load_command('airflow.cli.commands.provider_command.hooks_list'),
        args=(ARG_OUTPUT, ARG_VERBOSE),
    ),
    ActionCommand(
        name='behaviours',
        help='Get information about registered connection types with custom behaviours',
        func=lazy_load_command('airflow.cli.commands.provider_command.connection_field_behaviours'),
        args=(ARG_OUTPUT, ARG_VERBOSE),
    ),
)
USERS_COMMANDS = (
    ActionCommand(
        name='list',
        help='List users',
        func=lazy_load_command('airflow.cli.commands.user_command.users_list'),
        args=(ARG_OUTPUT, ARG_VERBOSE),
    ),
    ActionCommand(