未捕获的错误:在将laravel 5.8升级到8之后调用未定义的函数laravel\Mail\TransportManager()

use Laravel\Mail\TransportManager;

$manager = new TransportManager();

use Illuminate\Mail\TransportManager;

$manager = app()->make(TransportManager::class);

use Illuminate\Support\Facades\Mail;
use App\Mail\ExampleMail;

Mail::to('recipient@example.com')->send(new ExampleMail());

composer update

use Laravel\Mail\TransportManager;

class MailService
{
    public function sendMail()
    {
        $manager = new TransportManager();
        // 其他逻辑
    }
}

use Illuminate\Mail\TransportManager;

class MailService
{
    public function sendMail()
    {
        $manager = app()->make(TransportManager::class);
        // 其他逻辑
    }
}

use Illuminate\Support\Facades\Mail;
use App\Mail\ExampleMail;

class MailService
{
    public function sendMail()
    {
        Mail::to('recipient@example.com')->send(new ExampleMail());
    }
}