docs: @BetaApi
    public final Operation deleteBackendBucket(ProjectGlobalBackendBucketName backendBucket) {
  
      DeleteBackendBucketHttpRequest request =
          DeleteBackendBucketHttpRequest.newBuilder()
              .setBackendBucket(backendBucket == null ? null : backendBucket.toString())
              .build();
      return deleteBackendBucket(request);
    }