Expand Designate RBAC testing - zones

This patch adds RBAC testing for allowed and disallowed credentials.
This is one of a series of patches adding testing. This patch covers the
zones API.

Change-Id: I2312e0e4293b60d9644f8c0d3a41e0b5f330c20d
diff --git a/designate_tempest_plugin/tests/base.py b/designate_tempest_plugin/tests/base.py
index 9035c83..e581e0a 100644
--- a/designate_tempest_plugin/tests/base.py
+++ b/designate_tempest_plugin/tests/base.py
@@ -67,9 +67,10 @@
     # have cls.os_alt, and admin will have cls.os_admin.
     # NOTE(johnsom) We will allocate most credentials here so that each test
     # can test for allowed and disallowed RBAC policies.
-    credentials = ['admin', 'primary']
+    credentials = ['admin', 'primary', 'alt']
     if CONF.dns_feature_enabled.enforce_new_defaults:
-        credentials.extend(['system_admin', 'system_reader', 'project_reader'])
+        credentials.extend(['system_admin', 'system_reader',
+                            'project_member', 'project_reader'])
 
     # A tuple of credentials that will be allocated by tempest using the
     # 'credentials' list above. These are used to build RBAC test lists.