test sending booking do to email

app/Http/Controllers/InvoiceController.php

@@ -3,6 +3,7 @@
 namespace App\Http\Controllers;
 
 use Illuminate\Http\Request;
+use Illuminate\Mail\Mailer;
 use Illuminate\Support\Facades\File;
 use Illuminate\Support\Facades\Mail;
 use Illuminate\Validation\Rule;
@@ -373,6 +374,7 @@ class InvoiceController extends Controller
                 $message->subject('DO for bookings on'.Carbon::today());
 
                 $message->attachData($attachment, 'do_'.Carbon::today()->format('Y_m_d').'.zip', [
+                    'as' => 'do_'.Carbon::today()->format('Y_m_d').'.zip',
                     'mime' => 'application/zip',
                 ]);
             });