fix: Use internal barbican endpoint type (#642)

By default the barbican client in cinder uses `public`, but that is not
ideal for communication between cinder and barbican in a local cluster.
Update this to be internal, as public comms might not work in some
environments by design.

base-helm-configs/cinder/cinder-helm-overrides.yaml

@@ -803,6 +803,8 @@ conf:
       use_multipath_for_image_xfer: False #Add Cinder Multipath support for image xfer
     database:
       max_retries: -1
+    barbican:
+      barbican_endpoint_type: internal
     key_manager:
       backend: barbican
     keystone_authtoken: