Keep new RBAC disable by default

oslo.policy has enabled the new RBAC config options
enforce_scope and enforce_new_defaults by default[1][2].

There are more changes (test fixes also) needed to make
Horizon work with new RBAC. Some of the required changes
can be seen in the below changes:
- https://zuul.opendev.org/t/openstack/build/dad4aacd73ae4eee8dc58fced1730732
- https://review.opendev.org/c/openstack/horizon/+/927341
- https://review.opendev.org/c/openstack/horizon/+/927342

NOTE: Horizon has not enabled the new BRAC yet so there is
no change in behaviour in this release.

Needed-By: https://review.opendev.org/c/openstack/requirements/+/925464

[1] https://review.opendev.org/c/openstack/oslo.policy/+/924283
[2] https://review.opendev.org/c/openstack/releases/+/925032

Change-Id: Idfe9336df9f98badc1773a07c848b521a1323f3e

openstack_auth/policy.py

@@ -35,7 +35,12 @@ def _get_policy_conf(policy_file, policy_dirs=None):
     conf = cfg.ConfigOpts()
     # Passing [] is required. Otherwise oslo.config looks up sys.argv.
     conf([])
-    policy_opts.set_defaults(conf)
+    # TODO(gmann): Remove setting the default value of 'enforce_scope'
+    # and 'enforce_new_defaults' once Horizon is ready with the
+    # new RBAC (oslo_policy enabled them by default).
+    policy_opts.set_defaults(conf,
+                             enforce_scope=False,
+                             enforce_new_defaults=False)
     conf.set_default('policy_file', policy_file, 'oslo_policy')
     # Policy Enforcer has been updated to take in a policy directory
     # as a config option. However, the default value in is set to