Fix airflowctl connections create-defaults command

[Prab-27]

airflowctl connections create-defaults shows

Traceback (most recent call last):
  File "/usr/python/bin/airflowctl", line 10, in <module>
    sys.exit(main())
  File "/opt/airflow/airflow-ctl/src/airflowctl/__main__.py", line 34, in main
    safe_call_command(args.func, args=args)
  File "/opt/airflow/airflow-ctl/src/airflowctl/ctl/cli_config.py", line 77, in safe_call_command
    function(args)
  File "/opt/airflow/airflow-ctl/src/airflowctl/api/client.py", line 531, in wrapper
    return func(*args, api_client=api_client, **kwargs)
  File "/opt/airflow/airflow-ctl/src/airflowctl/ctl/cli_config.py", line 772, in _get_func
    data=check_operation_and_collect_list_of_dict(
  File "/opt/airflow/airflow-ctl/src/airflowctl/ctl/cli_config.py", line 751, in check_operation_and_collect_list_of_dict
    if is_dict_nested(dict_obj):
  File "/opt/airflow/airflow-ctl/src/airflowctl/ctl/cli_config.py", line 749, in is_dict_nested
    return any(isinstance(i, dict) or isinstance(i, list) for i in obj.values())
AttributeError: 'NoneType' object has no attribute 'values'

Now (after fixed):
Create-default connections and shows
[{"operation": "create_defaults", "status": "success"}]

---

Was generative AI tooling used to co-author this PR?

• Yes (copilot)

---

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