[B5] Bug while deleting custom emojis

Steps to Reproduce the Bug:

1. Update Invision to version 5.
2. Navigate to the Editor tab.
3. Select the Emojis section.
4. Click on Delete Set.
5. The bug occurs during this action.

TypeError: IPS\File::get(): Argument #2 ($url) must be of type IPS\Http\Url|string, null given, called in public_html/applications/core/modules/admin/editor/emoticons.php on line 393 (0)
#0 public_html/applications/core/modules/admin/editor/emoticons.php(393): IPS\File::get()
#1 public_html/system/Dispatcher/Controller.php(128): IPS\core\modules\admin\editor\emoticons->deleteSet()
#2 public_html/applications/core/modules/admin/editor/emoticons.php(70): IPS\Dispatcher\Controller->execute()
#3 public_html/system/Dispatcher/Dispatcher.php(169): IPS\core\modules\admin\editor\emoticons->execute()
#4 public_html/admin/index.php(15): IPS\Dispatcher->run()
#5 {main}

#0 public_html/init.php(827): IPS\Log::log()
#1 [internal function]: IPS\IPS::exceptionHandler()
#2 {main}