Description of problem: IPv6 provisioning job failing at introspection with
 "Internal server error (ValueError): Invalid IPv6 URL"


Version-Release number of selected component (if applicable):


How reproducible:
every time


Steps to Reproduce:
1. 
2.
3.

Actual results:
Introspection fails

Expected results:
Introspection succeeds

Additional info:
During:
PLAY [Baremetal Introspection for multiple Ironic Nodes]

the first error in the logs is:

ERROR os_tripleo_baremetal_node_introspection: Introspection of node 4985e539-d5be-41b9-b338-45f249f82994 failed on attempt 1: Node 4985e539-d5be-41b9-b338-45f249f82994 reached failure state \"inspect failed\"; the last error is Failed to start inspection: The baremetal-introspection service for 2620:dead:beef:4::3:regionOne exists but does not have any supported versions.",

and the final error is:
"Internal server error (ValueError): Invalid IPv6 URL"