### Body

The CLI:

`airflow variables set [-h] [-j] [-v] key VALUE`

https://airflow.apache.org/docs/apache-airflow/stable/cli-and-env-variables-ref.html#set_repeat1

Doesn't support adding description though column exists and we support it from Rest API:
https://airflow.apache.org/docs/apache-airflow/stable/stable-rest-api-ref.html#operation/post_variables

**The Task:**

Allow to set description from cli command

### Committer

- [X] I acknowledge that I am a maintainer/committer of the Apache Airflow project.
func=lazy_load_command("airflow.cli.commands.config_command.show_config"),
        args=(
            ARG_OPTIONAL_SECTION,
            ARG_COLOR,
            ARG_INCLUDE_DESCRIPTIONS,
            ARG_INCLUDE_EXAMPLES,
            ARG_INCLUDE_SOURCES,
            ARG_INCLUDE_ENV_VARS,
            ARG_COMMENT_OUT_EVERYTHING,
            ARG_EXCLUDE_PROVIDERS,
            ARG_DEFAULTS,
            ARG_VERBOSE,
        ),
    ),
)
KUBERNETES_COMMANDS = (
    ActionCommand(
        name="cleanup-pods",
        help=(
            "Clean up Kubernetes pods "
            "(created by KubernetesExecutor/KubernetesPodOperator) "
            "in evicted/failed/succeeded/pending states"
        ),
        func=lazy_load_command("airflow.cli.commands.kubernetes_command.cleanup_pods"),
        args=(ARG_NAMESPACE, ARG_MIN_PENDING_MINUTES, ARG_VERBOSE),
    ),
    ActionCommand(
        name="generate-dag-yaml",
        help="Generate YAML files for all tasks in DAG. Useful for debugging tasks without "
        "launching into a cluster",