message: Fix Kokoro breakage by using initializer list.
diff: @@ -441,7 +441,7 @@ TEST_F(CollectiveParamResolverLocalTest, AbortNormalCompleteParamsAsync) {
  // code to explicitly test every possible scenarios, so we run the test for
  // many times to have a better chance to cover different cases.
  CancellationManager cancel_mgr;
  - std::atomic<int64> num_ok = 0;
  + std::atomic<int64> num_ok{0};
  for (int cnt = 0; cnt < 100; ++cnt) {
  // Launching threads that keep doing CompleteInstanceLocal.
  BlockingCounter done(NUM_DEVS);
  