Move v3 inherited_roles_client to library interface

v3 inherited_roles_client is stable now and good to be moved
as stable library interface.

Partially implements blueprint consistent-service-method-names

Change-Id: I88b972d72b7ad5c2f4ee14ea2ddae0c03b8eaedf
diff --git a/releasenotes/notes/add-new-identity-clients-as-library-5f7ndha733nwdsn9.yaml b/releasenotes/notes/add-new-identity-clients-as-library-5f7ndha733nwdsn9.yaml
index 2e387a4..c2742a3 100644
--- a/releasenotes/notes/add-new-identity-clients-as-library-5f7ndha733nwdsn9.yaml
+++ b/releasenotes/notes/add-new-identity-clients-as-library-5f7ndha733nwdsn9.yaml
@@ -10,3 +10,4 @@
       * users_client(v3)
       * identity_client(v3)
       * roles_client(v3)
+      * inherited_roles_client(v3)