Undefined array key "authentication-results" with PHP 8.2

[gunnarhaslinger]

Using authres_status with PHP 8.2 leads to regular roundcubemail errors.log Entries:
PHP Warning: Undefined array key "authentication-results" in /var/www/roundcubemail/roundcubemail-current/plugins/authres_status/authres_status.php on line 339

Line 339 on my system is:
$hasAuthenticationResultHeaders = (bool)$headers->others['authentication-results'];

which is identical in the most current dev-master:

authres_status/authres_status.php

Line 339 in c5ba704

$hasAuthenticationResultHeaders = (bool)$headers->others['authentication-results'];

[pikachurus]

you can use 'isset' to override "Undefined array" warning:
$hasAuthenticationResultHeaders = (bool) isset($headers->others['authentication-results']);