In PHP 8.2:
```
$ arc unit --everything
FAIL PhabricatorMetaMTAReceivedMailTestCase::testDropSelfMail
EXCEPTION (RuntimeException): Use of "parent" in callables is deprecated
#0 /var/www/phorge/src/applications/metamta/exception/PhabricatorMetaMTAReceivedMailProcessingException.php(17): PhutilErrorHandler::handleError(8192, '...', '...', 17)
#1 /var/www/phorge/src/applications/metamta/storage/PhabricatorMetaMTAReceivedMail.php(368): PhabricatorMetaMTAReceivedMailProcessingException->__construct('...', '...')
#2 /var/www/phorge/src/applications/metamta/storage/PhabricatorMetaMTAReceivedMail.php(151): PhabricatorMetaMTAReceivedMail->dropMailFromPhabricator()
#3 /var/www/phorge/src/applications/metamta/storage/__tests__/PhabricatorMetaMTAReceivedMailTestCase.php(19): PhabricatorMetaMTAReceivedMail->processReceivedMail()
#4 /var/www/arcanist/src/unit/engine/phutil/PhutilTestCase.php(634): PhabricatorMetaMTAReceivedMailTestCase->testDropSelfMail()
#5 /var/www/arcanist/src/unit/engine/PhutilUnitTestEngine.php(69): PhutilTestCase->run()
#6 /var/www/arcanist/src/unit/engine/ArcanistConfigurationDrivenUnitTestEngine.php(148): PhutilUnitTestEngine->run()
#7 /var/www/arcanist/src/workflow/ArcanistUnitWorkflow.php(170): ArcanistConfigurationDrivenUnitTestEngine->run()
#8 /var/www/arcanist/scripts/arcanist.php(427): ArcanistUnitWorkflow->run()
#9 {main}
```