Yii2 unit testing :: Access denied for user 'something'@'localhost' (using password: NO)

When creating automated testing in unit testing. I get this error.

My code is in unit test

 function testSavingUser()
{
    $user = new User();
    $user->auth_key='Yasar Arafath';
    $user->password_hash='Yasar Arafath';
    $user->password_reset_token='Yasar Arafath';
    $user->email='Yasar Arafath';
    $user->status=1;
    $user->first_name='Yasar Arafath';
    $user->last_name='Yasar Arafath';
    $user->image='Yasar Arafath';
    $user->role_id=1;
    $user->created_date='2016-08-31 16:57:10';
    $user->updated_date='2016-08-31 16:57:10';

    $user->save();
    $this->assertEquals('Miles Davis', $user->getFullName());
    $this->tester->seeInDatabase('users', ['name' => 'Miles', 'surname' => 'Davis']);
}

This my config file

    $config =  yii\helpers\ArrayHelper::merge(
    require(__DIR__ . '/web.php'),
    //require(__DIR__ . '/main-local.php'),
    [
        'id' => 'app-tests',
        'components' => [
            'db' => [
                'class' => 'yii\db\Connection',
                'dsn' => 'mysql:host=' . getenv('DB_HOST'). ';dbname=' . getenv('DB_NAME'),
                'username' => getenv('DB_USER'),
                'password' => getenv('DB_PASSWORD'),
                'charset' => 'utf8',
            ],
        ]        
    ]
);
return $config;

In functional.suite.yml

class_name: FunctionalTester
    modules:
      enabled:
         - Yii2:
             configFile: 'config/test.php'

When trying to execute my test with codecept run it shows error like this

[yii\db\Exception] SQLSTATE[28000] [1045] Access denied for user 'yasar'@'localhost' (using password: NO)