**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
)
ARG_DEBUG = Arg(
    ("-d", "--debug"), help="Use the server that ships with Flask in debug mode", action="store_true"
)
ARG_ACCESS_LOGFILE = Arg(
    ("-A", "--access-logfile"),
    default=conf.get('webserver', 'ACCESS_LOGFILE'),
    help="The logfile to store the webserver access log. Use '-' to print to stderr",
)
ARG_ERROR_LOGFILE = Arg(
    ("-E", "--error-logfile"),
    default=conf.get('webserver', 'ERROR_LOGFILE'),
    help="The logfile to store the webserver error log. Use '-' to print to stderr",
)
ARG_ACCESS_LOGFORMAT = Arg(
    ("-L", "--access-logformat"),
    default=conf.get('webserver', 'ACCESS_LOGFORMAT'),
    help="The access log format for gunicorn logs",
)
ARG_NUM_RUNS = Arg(
    ("-n", "--num-runs"),
    default=conf.getint('scheduler', 'num_runs'),
    type=int,
    help="Set the number of runs to execute before exiting",
)
ARG_DO_PICKLE = Arg(
    ("-p", "--do-pickle"),
    default=False,
    help=(
        "Attempt to pickle the DAG object to send over "