Creation of dynamic property PhabricatorAuthPasswordException::$confirmError is deprecated

FAIL  PhabricatorAuthPasswordTestCase::testPasswordBlocklisting
EXCEPTION (RuntimeException): Creation of dynamic property PhabricatorAuthPasswordException::$confirmError is deprecated
#0 /var/www/phorge/src/applications/auth/password/PhabricatorAuthPasswordException.php(15): PhutilErrorHandler::handleError(8192, '...', '...', 15)
#1 /var/www/phorge/src/applications/auth/engine/PhabricatorAuthPasswordEngine.php(70): PhabricatorAuthPasswordException->__construct('...', '...')
#2 /var/www/phorge/src/applications/auth/__tests__/PhabricatorAuthPasswordTestCase.php(166): PhabricatorAuthPasswordEngine->checkNewPassword(Object(PhutilOpaqueEnvelope), Object(PhutilOpaqueEnvelope))
#3 /var/www/phorge/src/applications/auth/__tests__/PhabricatorAuthPasswordTestCase.php(152): PhabricatorAuthPasswordTestCase->assertBlocklistedPassword(Object(PhabricatorAuthPasswordEngine), '', false)
#4 /var/www/arcanist/src/unit/engine/phutil/PhutilTestCase.php(634): PhabricatorAuthPasswordTestCase->testPasswordBlocklisting()
#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}

<?php
error_reporting(E_ALL);

class User {
    public function __construct() {
        $this->name = 'test';
    }
}

new User();

<?php
error_reporting(E_ALL);

class User {

+   private $name;

    public function __construct() {
        $this->name = 'test';
    }
}

new User();