Switch copyright holder to "Google LLC" (#4287)

diff --git a/tests/unit/operations_v1/test_operations_client.py b/tests/unit/operations_v1/test_operations_client.py
index 60b11b7..1b6e6d9 100644
--- a/tests/unit/operations_v1/test_operations_client.py
+++ b/tests/unit/operations_v1/test_operations_client.py
@@ -1,4 +1,4 @@
-# Copyright 2017 Google Inc.
+# Copyright 2017 Google LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.