@Provides
  @Singleton
  Bucket getBucket(@ProjectId String projectId) {
    Storage storage = StorageOptions.getDefaultInstance().getService();
    // Must match BUCKET_NAME for user data bucket in setup_gke_environment.sh
    String bucketId = "user-data-" + projectId;
    return storage.get(bucketId);
  }
Return the {@link Environment} we are running in based on our convention of Project ID's ending
in "-" followed by lower-case environment name.

<p>Throws {@link IllegalArgumentException} if projectId does not have a valid environment
suffix.
extensions/cloud/portability-cloud-google/src/main/java/org/datatransferproject/cloud/google/GoogleCloudExtensionModule.java