Undercloud post-update validations fail for unhealthy overcloud with pre-provisioned nodes

Issue

• openstack undercloud upgrade command fails to validate the outcome if overcloud with pre-provisioned nodes is in *_FAILED state
• Undercloud upgrade fails validation step if overcloud is unhealthy

2019-12-31 13:47:24,554 ERROR: ERROR error running the validation groups ['post-upgrade']   Mistral execution ID: b8409750-2505-4bca-8a2d-2b98fe65f3ac
2019-12-31 13:47:24,555 INFO:
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Undercloud upgrade complete.

The file containing this installation's passwords is at
/home/stack/undercloud-passwords.conf.

There is also a stackrc file at /home/stack/stackrc.

These files are needed to interact with the OpenStack services, and should be
secured.

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