[jb] Properly point to the correct node managers when fetching logs

class Attempt:
  ...
  def get_task_log(self, offset=0):
    logs = []
    attempt = self.task.job.job_attempts['jobAttempt'][-1]
    log_link = attempt['logsLink']

    # Generate actual task log link from logsLink url
    if self.task.job.status in ('NEW', 'SUBMITTED', 'RUNNING'):
      ...
    else:  # Completed jobs
      logs_path = '/jobhistory/logs/'
      root_url, tracking_path = log_link.split(logs_path)
      node_url, container_id, attempt_id, user = tracking_path.strip('/').split('/')

      # Replace log path tokens with actual attempt properties if available
      if hasattr(self, 'nodeHttpAddress') and 'nodeId' in attempt:
        node_url = '%s:%s' % (self.nodeHttpAddress.split(':')[0], attempt['nodeId'].split(':')[1])