"HTTP Error 403: Forbidden"

[Eder-K]

Attempting to trigger a systemtest from an external adapter repository using trigger_systemtest.py results in an error.

Error log:

Traceback (most recent call last):
  File "trigger_systemtests.py", line 288, in <module>
    = False), args.owner, 'systemtests' )
  File "trigger_systemtests.py", line 199, in trigger_travis_and_wait_and_respond
    json_response = trigger_travis_build(job_body, user, repo)
  File "trigger_systemtests.py", line 176, in trigger_travis_build
    return get_json_response(url, data = data)
  File "trigger_systemtests.py", line 37, in get_json_response
    response = urlopen( req ).read().decode()
  File "/opt/python/3.5.6/lib/python3.5/urllib/request.py", line 163, in urlopen
    return opener.open(url, data, timeout)
  File "/opt/python/3.5.6/lib/python3.5/urllib/request.py", line 472, in open
    response = meth(req, response)
  File "/opt/python/3.5.6/lib/python3.5/urllib/request.py", line 582, in http_response
    'http', request, response, code, msg, hdrs)
  File "/opt/python/3.5.6/lib/python3.5/urllib/request.py", line 510, in error
    return self._call_chain(*args)
  File "/opt/python/3.5.6/lib/python3.5/urllib/request.py", line 444, in _call_chain
    result = func(*args)
  File "/opt/python/3.5.6/lib/python3.5/urllib/request.py", line 590, in http_error_default
    raise HTTPError(req.full_url, code, msg, hdrs, fp)
urllib.error.HTTPError: HTTP Error 403: Forbidden