Prestage Orchestration - inconsistent state reporting for skipped subclouds

[Kyle MacLeod]

Brief Description
-----------------
Prestage Orchestration - Non-AIO-SX subclouds shows state complete for prestage

Note: it could show as complete, but we need a details message saying that the non-AIO-SX subcloud will be skipped for prestage

Severity
--------
Minor

Steps to Reproduce
------------------
Create a prestag-strategy for a group of subclouds which contains non-AIO-SX subclouds

Expected Behavior
------------------
Non-AIO-SX subclouds should be skipped and the details message field should have the reason why the subcloud was NOT prestaged.

Actual Behavior
----------------
state shows as 'complete'

Reproducibility
---------------
Reproducible

System Configuration
--------------------
Distributed Cloud system

Branch/Pull Time/Commit
-----------------------
latest starlingx master

Last Pass
---------
This is a new test scenario

Timestamp/Logs
--------------
Not required

Test Activity
-------------
Feature testing

Workaround
----------
n/a

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/c/starlingx/distcloud/+/832286

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/starlingx/distcloud/+/832286
Committed: https://opendev.org/starlingx/distcloud/commit/9c4d1e9965ffccd9ce7b53e82dbe7b84c3b89f61
Submitter: "Zuul (22348)"
Branch: master

commit 9c4d1e9965ffccd9ce7b53e82dbe7b84c3b89f61
Author: Kyle MacLeod <email address hidden>
Date: Mon Mar 7 11:34:00 2022 -0500

    Fix prestage orchestration details for skipped subclouds

    Ensure that the 'details' field reflects the reason a subcloud is
    skipped during prestage orchestration.

    We use a new exception, StrategySkippedException, to signal the
    OrchThread that a subcloud is being skipped. This immediately
    transitions the subcloud strategy to complete, while preserving
    the reason for skipping in the strategy_step details.

    NOTE: this update also includes a minor update
    to the API parameters file, which was missed in the
    original feature commit (api-ref/source/parameters.yaml)

    Test Plan:

    PASS:
    - normal prestage orchestration
    - prestage orchestration with non-AIO-SX subcloud
        - subcloud is skipped
        - details populated and reported in details column
          of 'dcmanager strategy-step list'
        - subcloud deploy_status is returned to 'complete'
    - verify feature logging

    Closes-Bug: 1963967
    Signed-off-by: Kyle MacLeod <email address hidden>
    Change-Id: I3408f274e3e04410872716b718130a3a27006c36

[Ghada Khalil (gkhalil)]

screening: stx.7.0 / medium - related to new feature development: https://storyboard.openstack.org/#!/story/2009799