Including another web.php file in config/web.php of yii2

We are two groups developing a project made in Yii2 basic. The problem we are facing right now is we have different web.php under config. Our group would like to include our web.php (which was renamed to extras.php) inside the web.php of another group. The difference is we added variables under components of $config of web.php. Yes, we can manually add our new variables under components of $config from the other team but we prefer to use separate files that is why we renamed the other web.php to extras.php.

A small preview of web.php looks like this

$params = require(__DIR__ . '/params.php');

$config = [
    'id' => 'basic',
    'basePath' => dirname(__DIR__),
    'bootstrap' => ['log'],
    'language'=>  isset($_SESSION['language_local']) ? $_SESSION['language_local']:'en',
    'components' => [
        'nagios' => [
                    'class' =>  'app\components\nagios',
        ],
        'hostlistsql' => [
                   'class' =>  'app\components\hostlistsql',
        ],
        'request' => [empty) - this is required by cookie validation
            'cookieValidationKey' => 'nYwdMpu-dw004qwFRZmqZOzzC3xdnL8b',
        ],
        'cache' => [
            'class' => 'yii\caching\FileCache',
        ],
    ],
    'params' => $params,
];

extras.php looks like this

$params = require(__DIR__ . '/params.php');

$config = [
    'id' => 'basic',
    'basePath' => dirname(__DIR__),
    'bootstrap' => ['log'],
    'language'=>  isset($_SESSION['language_local']) ? $_SESSION['language_local']:'en',
    'components' => [
        'user_functions' => [
                    'class' =>  'app\components\UserFunctions',
        ],
        'user_extras' => [
                   'class' =>  'app\components\UserExtras',
        ],
        'request' => [empty) - this is required by cookie validation
            'cookieValidationKey' => 'nYwdMpu-dw004qwFRZmqZOzzC3xdnL8b',
        ],
        'cache' => [
            'class' => 'yii\caching\FileCache',
        ],
    ],
    'params' => $params,
];

What approach should we take to include extras.php inside web.php?