Fix ordering of tags in the OCI model

Before this change, we were neglecting to sort the tags by ID, which meant that pagination was broken

endpoints/v2/tag.py

@@ -21,7 +21,7 @@ def list_all_tags(namespace_name, repo_name, start_id, limit, pagination_callbac
   # NOTE: We add 1 to the limit because that's how pagination_callback knows if there are
   # additional tags.
   tags = registry_model.list_repository_tags(repository_ref, start_pagination_id=start_id,
-                                             limit=limit + 1)
+                                             limit=limit + 1, sort_tags=True)
   response = jsonify({
     'name': '{0}/{1}'.format(namespace_name, repo_name),
     'tags': [tag.name for tag in tags][0:limit],