Remove usage of ineffective parameter in nova::api class
Remove usage of ineffective parameter in nova::api class

The nova::api::neutron_metadata_proxy_shared_secret parameter was
already removed from puppet-nova[1], so we should remove that parameter
from t-h-t as well.

[1] 66f2e8e509941391c172b56f5b9e4310e5fa72dd

Change-Id: I588c7c1cf44dc0c1794371d6ed4b0958071a8e2c

openstack/tripleo-heat-templates,openstack/tripleo-heat-templates