Remove retired karbor-dashboard usage
Remove retired karbor-dashboard usage

As announced on the openstack-discuss ML[1], Karbor is retiring
this cycle (Wallaby).

[1] http://lists.openstack.org/pipermail/openstack-discuss/2020-November/018643.html

Needed-By: https://review.opendev.org/c/openstack/karbor-dashboard/+/767034
Change-Id: I25ed212bbd244d0965c4a879c3a53e69805a5798

openstack/horizon,ChameleonCloud/horizon,ChameleonCloud/horizon,openstack/horizon,ChameleonCloud/horizon,openstack/horizon,openstack/horizon,ChameleonCloud/horizon