### 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.
)
ARG_FULL = Arg(
    ("-f", "--full"),
    help="Full information about the provider, including documentation information.",
    required=False,
    action="store_true",
)
ARG_ANONYMIZE = Arg(
    ("--anonymize",),
    help="Minimize any personal identifiable information. Use it when sharing output with others.",
    action="store_true",
)
ARG_FILE_IO = Arg(
    ("--file-io",), help="Send output to file.io service and returns link.", action="store_true"
)
ARG_SECTION = Arg(
    ("section",),
    help="The section name",
)
ARG_OPTION = Arg(
    ("option",),
    help="The option name",
)
ARG_OPTIONAL_SECTION = Arg(
    ("--section",),
    help="The section name",
)
ARG_NAMESPACE = Arg(
    ("--namespace",),
    default=conf.get("kubernetes_executor", "namespace"),