Unable to create a subcloud due I/O operation on closed file

[Hugo Nicodemos Brito]

Brief Description
-----------------
When the user tries to add a subcloud to the system controller an error occurs: ERROR (app) I/O operation on closed file

Severity
--------
<Critical: System/Feature is not usable due to the defect>

Steps to Reproduce
------------------
Execute: dcmanager subcloud add --bootstrap-values <config_file>

Expected Behavior
------------------
Subcloud created successfully

Actual Behavior
----------------
ERROR (app) I/O operation on closed file

Reproducibility
---------------
<Reproducible>

System Configuration
--------------------
All configurations

Branch/Pull Time/Commit
-----------------------
Master

Last Pass
---------
NA

Timestamp/Logs
--------------
NA

Test Activity
-------------
NA

Workaround
----------
NA

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/c/starlingx/distcloud-client/+/910653

[Ghada Khalil (gkhalil)]

Issue introduced by a recent commit: https://review.opendev.org/c/starlingx/distcloud-client/+/909454

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/starlingx/distcloud-client/+/910653
Committed: https://opendev.org/starlingx/distcloud-client/commit/d847780a4d179485bc76f57e56951ce380eae26a
Submitter: "Zuul (22348)"
Branch: master

commit d847780a4d179485bc76f57e56951ce380eae26a
Author: Hugo Brito <email address hidden>
Date: Thu Feb 29 14:25:49 2024 -0300

    Fix subcloud fields update

    This commit addresses the issue encountered when updating the
    subcloud fields directly with a file introduced by [1]. This
    caused issues because the file would be closed, making the content
    inaccessible. Now, we update the fields using the file content.

    An intermittent error, introduced by [2], was fixed in the
    test_prestage_with_subcloud_id test.

    [1]: https://review.opendev.org/c/starlingx/distcloud-client/+/909454
    [2]: https://review.opendev.org/c/starlingx/distcloud-client/+/909975

    Test Plan:
    PASS: Create a subcloud
    PASS: Update a subcloud
    PASS: Create a subcloud backup
    PASS: Subcloud deploy create
    PASS: Subcloud deploy upload

    Closes-bug: 2055446

    Change-Id: Ib8b831353dba9d073131eb1c12ccd57513c63e7f
    Signed-off-by: Hugo Brito <email address hidden>