We upgraded phabricator, arcanist, and libphutil last Friday. After adding our extensions, `bin/phd start` failed with
```PHP Fatal error: Class DropboxAddReviewersEnginePatched may not inherit from final class (DropboxAddReviewersEngine) in ..../phabricator/src/extensions/phabricator-extensions/contacts/herald/__tests__/DropboxAddReviewersEngineTest.php on line 15```
I'm confused why the phabricator daemons are loading the testfiles -- particularly as I can't get them to run with arc unit, when they're supposed to. (strace shows they're not even looking at the __test__ subdirectories).
What do you expect to be the minimal configuration is to run PhutilUnitTestEngine tests (aka __tests__ directories)?