I discovered testbed tests are failing to parse the jobs and input data into the tko database because they have multiple board labels:

Failed to retrieve board label from host labels: loopback-dongle,os%3Abrillo,board%3Adragonboard-2,board%3Adragonboard-1
Traceback (most recent call last):
  File "/usr/local/autotest/tko/parse.py", line 387, in parse_leaf_path
    mail_on_failure)
  File "/usr/local/autotest/tko/db.py", line 139, in run_with_retry
    result = function(*args, **dargs)
  File "/usr/local/autotest/tko/parse.py", line 213, in parse_one
    job = parser.make_job(path)
  File "/usr/local/autotest/tko/parsers/version_1.py", line 240, in make_job
    return job(dir)
  File "/usr/local/autotest/tko/parsers/version_0.py", line 18, in __init__
    job_dict = job.load_from_dir(dir)
  File "/usr/local/autotest/tko/parsers/version_0.py", line 33, in load_from_dir
    machine_group = cls.determine_machine_group(machine, dir)
  File "/usr/local/autotest/tko/parsers/version_0.py", line 91, in determine_machine_group
    raise BoardLabelError(error)
BoardLabelError: Failed to retrieve board label from host labels: loopback-dongle,os%3Abrillo,board%3Adragonboard-2,board%3Adragonboard-1