RBAC tests for extended server attributes policies

This commit adds RBAC tests for extended server attributes
policies, the documentation for which can be found here:

https://github.com/openstack/nova/blob/master/nova/policies/extended_server_attributes.py

Tests for both APIs that enforce each policy were added.

Change-Id: I4150bcff934f1386ba8947d271289b790900ce2e
Implements: blueprint rbac-tests-for-extended-server-attributes
diff --git a/releasenotes/notes/extended-server-attributes-36623af87e714369.yaml b/releasenotes/notes/extended-server-attributes-36623af87e714369.yaml
new file mode 100644
index 0000000..a7ccd8e
--- /dev/null
+++ b/releasenotes/notes/extended-server-attributes-36623af87e714369.yaml
@@ -0,0 +1,5 @@
+---
+features:
+  - |
+    Add complete RBAC test coverage for the compute APIs that enforce:
+    "os_compute_api:os-extended-server-attributes".