Move the object client to tempest.lib

Move the object client to tempest.lib and cleanup the last bits
of code that were required to manage internal-only tempest service
clients.

Change-Id: Ia9aeab78e530c798dfa7b7d6f71e4b3ea3a84b7f
diff --git a/releasenotes/notes/make-account-client-as-stable-interface-d1b07c7e8f17bef6.yaml b/releasenotes/notes/make-object-storage-client-as-stable-interface-d1b07c7e8f17bef6.yaml
similarity index 92%
rename from releasenotes/notes/make-account-client-as-stable-interface-d1b07c7e8f17bef6.yaml
rename to releasenotes/notes/make-object-storage-client-as-stable-interface-d1b07c7e8f17bef6.yaml
index 5f899cf..2bba952 100644
--- a/releasenotes/notes/make-account-client-as-stable-interface-d1b07c7e8f17bef6.yaml
+++ b/releasenotes/notes/make-object-storage-client-as-stable-interface-d1b07c7e8f17bef6.yaml
@@ -8,3 +8,4 @@
 
       * account_client
       * container_client
+      * object_client