Upgrade code - step 1

app/Jobs/QueuedClosure.php

@@ -4,7 +4,7 @@ namespace App\Jobs;
 
 use Closure;
 use Illuminate\Queue\CallQueuedClosure;
-use Illuminate\Queue\SerializableClosure;
+use Laravel\SerializableClosure\SerializableClosure;
 
 abstract class QueuedClosure extends CallQueuedClosure
 {
@@ -12,7 +12,7 @@ abstract class QueuedClosure extends CallQueuedClosure
     /**
      * Create a new job instance.
      *
-     * @param \Illuminate\Queue\SerializableClosure $closure
+     * @param \Laravel\SerializableClosure\SerializableClosure $closure
      */
     public function __construct(Closure $closure)
     {

app/Providers/AppServiceProvider.php

@@ -18,6 +18,8 @@ class AppServiceProvider extends ServiceProvider
      */
     public function register()
     {
+        $this->app->bind(\Illuminate\Contracts\Foundation\MaintenanceMode::class, \Illuminate\Foundation\MaintenanceModeManager::class);
+
         $this->app->bind(WorkCommand::class, function ($app) {
             $isDownForMaintenance = function () {
                 return $this->app->isDownForMaintenance();