We were assuming that env.SupervisorHTTPAddress was set, but it might not be
depending on the environment on which the integration tests are being run. For
example, in our acceptance environments, we don't currently set
env.SupervisorHTTPAddress.
I tried to follow the pattern from TestSupervisorOIDCDiscovery here.
Signed-off-by: Andrew Keesler <akeesler@vmware.com>