Several Flow tests fail randomly, see traces below; a recheck always solves the problem.
08:42:12 1) Flow\Tests\Collection\PostCollectionTest::testGetFirstRevision 08:42:12 Failed asserting that false is true. 08:42:12 08:42:12 /workspace/src/extensions/Flow/tests/phpunit/Collection/PostCollectionTest.php:90 08:42:12 /workspace/src/tests/phpunit/MediaWikiTestCase.php:424 08:42:12 /workspace/src/maintenance/doMaintenance.php:94
23:02:04 1) Flow\Tests\Api\ApiFlowModerateTopicTest::testModerateLockedTopic
23:02:04 Wikimedia\Rdbms\DBQueryError: A database query error has occurred. Did you forget to run your application's database schema updater after upgrading?
23:02:04 Query: INSERT INTO `unittest_flow_revision` (rev_id,rev_user_id,rev_user_ip,rev_user_wiki,rev_parent_id,rev_change_type,rev_type,rev_type_id,rev_content,rev_flags,rev_mod_state,rev_mod_user_id,rev_mod_user_ip,rev_mod_user_wiki,rev_mod_timestamp,rev_mod_reason,rev_last_edit_id,rev_edit_user_id,rev_edit_user_ip,rev_edit_user_wiki,rev_content_length,rev_previous_content_length) VALUES ('�z#p�4:��','1',NULL,'wikidb-unittest_','�z#p��4:��','delete-topic','post','�z#p��4:��','Hi there!','utf-8,topic-title-wikitext','delete','1',NULL,'wikidb-unittest_','20181116215905','<>&{};',NULL,NULL,NULL,NULL,'0','9')
23:02:04 Function: Flow\Data\Storage\RevisionStorage::insert
23:02:04 Error: 1062 Duplicate entry '\x05\x9Cz#p\xA3\xFE4:\x9C\xED' for key 'flow_revision_unique_parent' (/workspace/db/quibble-mysql-a08yeqot/socket)