Allow get_tenant_network() for non-primary creds

Within get_tenant_network(), a client manager was always retrieved, but
because no arguments were passed, it always retrieved the client manager
for the primary credentials. The credentials for the tenant network to
retrieve needs to be passed in so the appropriate client manager can be
retrieved.

Change-Id: I1b20259fc4418d722ed4144e156607ec2a667c33
Closes-Bug: #1549381
2 files changed