### Description

Currently, the `airflow variables export` command requires an explicit file path and does not support output to stdout. However connections can be printed to stdout using `airflow connections export -`. This inconsistency between the two export commands can lead to confusion and limits the flexibility of the variables export command.

### Use case/motivation

To bring some consistency, similar to connections, variables should also be printed to STDOUT, using `-` instead of filename. 

### Related issues

_No response_

### Are you willing to submit a PR?

- [X] Yes I am willing to submit a PR!

### Code of Conduct

- [X] I agree to follow this project's [Code of Conduct](https://github.com/apache/airflow/blob/main/CODE_OF_CONDUCT.md)

args=tuple(),
    ),
]
if _ENABLE_AIP_44:
    core_commands.append(
        ActionCommand(
            name="internal-api",
            help="Start a Airflow Internal API instance",
            func=lazy_load_command("airflow.cli.commands.internal_api_command.internal_api"),
            args=(
                ARG_INTERNAL_API_PORT,
                ARG_INTERNAL_API_WORKERS,
                ARG_INTERNAL_API_WORKERCLASS,
                ARG_INTERNAL_API_WORKER_TIMEOUT,
                ARG_INTERNAL_API_HOSTNAME,
                ARG_PID,
                ARG_DAEMON,
                ARG_STDOUT,
                ARG_STDERR,
                ARG_INTERNAL_API_ACCESS_LOGFILE,
                ARG_INTERNAL_API_ERROR_LOGFILE,
                ARG_INTERNAL_API_ACCESS_LOGFORMAT,
                ARG_LOG_FILE,
                ARG_SSL_CERT,
                ARG_SSL_KEY,
                ARG_DEBUG,
            ),
        ),
    )
def _remove_dag_id_opt(command: ActionCommand):