TestRoutes assumes that there is at least one vm in the OpenStack it
is connecting to. So let's limit this test to run properly only when
we are running in a VM or one was created already outside of the
test harness
This adds context to all the relevant cloud provider interface signatures.
Callers of those APIs are currently satisfied using context.TODO().
There will be follow on PRs to push the context through the stack.
For an idea of the full scope of this change please look at PR #58532.
This change implements the Routes API using Neutron's "extraroute"
extension.
To use, this requires all the nodes to be on the same Neutron network
and the UUID of the Neutron router on that network.
Required cloud provider config section:
[Route]
router-id = <UUID of Neutron router>
Ensure kube-controllermanager is started with (non-default)
`--allocate-node-cidrs=true` and set `--cluster-cidr` to the POD
super-subnet (a private /16 would be reasonable).
Based on an earlier version by @timbyr (#19473)
