private void downloadBlob(BlobId blobId) throws CloudStorageException {
    azureDest.downloadBlob(blobId, new ByteArrayOutputStream(blobSize));
  }
Download a blob with the given blobId.
@param blobId blobid of the blob to be downloaded.
ambry-cloud/src/test/java/com/github/ambry/cloud/azure/AzureCloudDestinationTest.java