Hard fail on failing to get machine name

[markusdregi]

Context
Error observed during CI.

Stacktrace

Traceback (most recent call last):
  File "/Users/runner/hostedtoolcache/Python/3.6.13/x64/bin/ert3", line 11, in <module>
    load_entry_point('ert==2.23rc2.dev13+g72c689ff', 'console_scripts', 'ert3')()
  File "/Users/runner/hostedtoolcache/Python/3.6.13/x64/lib/python3.6/site-packages/ert3/console/_console.py", line 203, in main
    _main()
  File "/Users/runner/hostedtoolcache/Python/3.6.13/x64/lib/python3.6/site-packages/ert3/console/_console.py", line 229, in _main
    _run(workspace, args)
  File "/Users/runner/hostedtoolcache/Python/3.6.13/x64/lib/python3.6/site-packages/ert3/console/_console.py", line 168, in _run
    args.experiment_name,
  File "/Users/runner/hostedtoolcache/Python/3.6.13/x64/lib/python3.6/site-packages/ert3/engine/_run.py", line 177, in run
    _evaluate(ensemble, stages_config, workspace_root, experiment_name)
  File "/Users/runner/hostedtoolcache/Python/3.6.13/x64/lib/python3.6/site-packages/ert3/engine/_run.py", line 156, in _evaluate
    workspace_root, experiment_name, parameters, ensemble, stages_config
  File "/Users/runner/hostedtoolcache/Python/3.6.13/x64/lib/python3.6/site-packages/ert3/evaluator/_evaluator.py", line 271, in evaluate
    config = EvaluatorServerConfig()
  File "/Users/runner/hostedtoolcache/Python/3.6.13/x64/lib/python3.6/site-packages/ert_shared/ensemble_evaluator/config.py", line 146, in __init__
    cert, key, pw = _generate_certificate(ip_address=self.host)
  File "/Users/runner/hostedtoolcache/Python/3.6.13/x64/lib/python3.6/site-packages/ert_shared/ensemble_evaluator/config.py", line 91, in _generate_certificate
    cert_name = get_machine_name()
  File "/Users/runner/hostedtoolcache/Python/3.6.13/x64/lib/python3.6/site-packages/ert_shared/ensemble_evaluator/config.py", line 58, in get_machine_name
    resolved_host = str(resolver.resolve(rev_name, "PTR")[0])
  File "/Users/runner/hostedtoolcache/Python/3.6.13/x64/lib/python3.6/site-packages/dns/resolver.py", line 1307, in resolve
    lifetime, search)
  File "/Users/runner/hostedtoolcache/Python/3.6.13/x64/lib/python3.6/site-packages/dns/resolver.py", line 1176, in resolve
    timeout = self._compute_timeout(start, lifetime)
  File "/Users/runner/hostedtoolcache/Python/3.6.13/x64/lib/python3.6/site-packages/dns/resolver.py", line 997, in _compute_timeout
    raise Timeout(timeout=duration)
dns.exception.Timeout: The DNS operation timed out after 5.020180940628052 seconds

Suggestion
We could for instance catch the Timeout, log the incident and try again a constant number of times before we take fire.