Rework socialite integration (#14367)

* Rework socialite integration

Prevents unnecessary work each boot

* Update SocialiteController.php

* Gen 2

app/Http/Controllers/Auth/SocialiteController.php

@@ -40,6 +40,7 @@ class SocialiteController extends Controller
 
     public function __construct()
     {
+        app()->register(\SocialiteProviders\Manager\ServiceProvider::class);
         $this->injectConfig();
     }