fix: admin and member gates are broken

The patrole-admin and patrole-member gates are broken because they
are trying to test a policy action ('os_compute_api:os-services') that
was changed in the Ussuri release. This commit adds a new policy feature
flag so that this policy test is backwards compatible.

Change-Id: Ia80279ae8ffcc17f10bed05338c41d0c23eea063
4 files changed