Amphora API returns the wrong topology in ACTIVE_STANDBY mode.

[Nir Magnezi]

Steps to Reproduce:
===================
1. Modify octavia.conf --> [controller_worker] --> loadbalancer_topology = ACTIVE_STANDBY
2. Restart Octavia services for changes to take effect.
3. Create a loadbalancer: neutron lbaas-loadbalancer-create --name test private-subnet
4. In admin tenant: verify that two amphora instances where created.
5. Check amphoras topology via API:

curl -k --cert /etc/octavia/certs/client.pem https://<amphora_a ip in lb-mgmt-net>:9443/0.5/details
curl -k --cert /etc/octavia/certs/client.pem https://<amphora_b ip in lb-mgmt-net>:9443/0.5/details

Response (in both cases): --> "topology": "SINGLE",

To the best of my knowledge, there is no other way to determine which amphora is active and which is standby.

Another problem which might be related is that both amphoras hold the VIP address in eth1:0.
I expected it to be the case only on the active one.