### 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.
),
    ActionCommand(
        name="reset",
        help="Burn down and rebuild the metadata database",
        func=lazy_load_command("airflow.cli.commands.db_command.resetdb"),
        args=(ARG_YES, ARG_DB_SKIP_INIT, ARG_VERBOSE),
    ),
    ActionCommand(
        name="upgrade",
        help="Deprecated -- use `migrate` instead. Upgrade the metadata database to latest version",
        description=(
            "Upgrade the schema of the metadata database. "
            "To print but not execute commands, use option ``--show-sql-only``. "
            "If using options ``--from-revision`` or ``--from-version``, you must also use "
            "``--show-sql-only``, because if actually *running* migrations, we should only "
            "migrate from the *current* Alembic revision."
        ),
        func=lazy_load_command("airflow.cli.commands.db_command.upgradedb"),
        args=(
            ARG_DB_REVISION__UPGRADE,
            ARG_DB_VERSION__UPGRADE,
            ARG_DB_SQL_ONLY,
            ARG_DB_FROM_REVISION,
            ARG_DB_FROM_VERSION,
            ARG_DB_RESERIALIZE_DAGS,
            ARG_VERBOSE,
        ),
        hide=True,
    ),
    ActionCommand(