Remove reference to Neutron LBaaS
Remove reference to Neutron LBaaS

Neutron LBaaS has been retired and there will be no Train release [1].
References to it should now be removed.

[1] https://review.opendev.org/#/c/658494/

Change-Id: I543694a97406241d86acacefe528b36c80bee214

ChameleonCloud/horizon,NeCTAR-RC/horizon,openstack/horizon,NeCTAR-RC/horizon,openstack/horizon,ChameleonCloud/horizon,openstack/horizon,ChameleonCloud/horizon,openstack/horizon,ChameleonCloud/horizon,NeCTAR-RC/horizon,NeCTAR-RC/horizon