NFV strategy create conflict should report what exists

[Al Bailey]

Brief Description
-----------------
If an existing VIM strategy has been built (or failed) and a new one is created, it reports a conflict but does not indicate which type exists.

Severity
--------
Minor

Steps to Reproduce
------------------
Create a patch strategy
 sw-manager patch-strategy create
Create another strategy (it can be the same type)
 sw-manager patch-strategy create

Expected Behavior
------------------
It should indicate failure so that the user knows how to resolve

Actual Behavior
----------------
It indicates failure , but you need to check every strategy type to see which one to delete

Reproducibility
---------------
100%

System Configuration
--------------------
AIO-SX

Branch/Pull Time/Commit
-----------------------
Sept 13 2022

Last Pass
---------
N/A This is an enhancement request

Timestamp/Logs
--------------
N/A

Test Activity
-------------
Developer Testing

Workaround
----------
Check (and delete) each strategy type
sw-manager patch-strategy show
sw-manager upgrade-strategy show
sw-manager kube-upgrade-strategy show
etc..

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/c/starlingx/nfv/+/857529

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/starlingx/nfv/+/857529
Committed: https://opendev.org/starlingx/nfv/commit/7ca02243d103a0f4380c3a347b9fdfae789537c1
Submitter: "Zuul (22348)"
Branch: master

commit 7ca02243d103a0f4380c3a347b9fdfae789537c1
Author: Al Bailey <email address hidden>
Date: Tue Sep 13 13:59:21 2022 +0000

    Adding details to VIM API Conflict responses

    When the VIM Stragegy API returns a 409 Conflict for a create,
    it is much more useful to know details about the conflict.
    ie: what type of strategy already exists.

    This fix required:
     - the strategy creation rpc message adds an error string
     - pecan.abort 'conflict' must include the error string
     - the nfv_client code must extract the error string
     - the strategy types must return knowledge of an existing
    strategy type
     - the director class must include details of the existing
    strategy type in its failure messages.

    Test Plan:
      PASS: Create two patch strategies and view the error.
      PASS: Create two different strategies and view the error.
      PASS: View errors when creating multiple strategies
           from horizon.

    Closes-Bug: #1989485
    Signed-off-by: Al Bailey <email address hidden>
    Change-Id: Ic79eab03b70b8bc7fbe2876f95eea3f2f34ab791