Warning logged: Source path aut has to start with a slash.

Problem

When invalid paths like /index.phpaut are accessed, a warning is logged like:

#0 /app/web/modules/contrib/anonymous_login/src/EventSubscriber/AnonymousLoginSubscriber.php(178): Drupal\path_alias\AliasManager->getAliasByPath()
#1 [internal function]: Drupal\anonymous_login\EventSubscriber\AnonymousLoginSubscriber->redirect()
#2 /app/web/core/lib/Drupal/Component/EventDispatcher/ContainerAwareEventDispatcher.php(111): call_user_func()
#3 /app/vendor/symfony/http-kernel/HttpKernel.php(157): Drupal\Component\EventDispatcher\ContainerAwareEventDispatcher->dispatch()
#4 /app/vendor/symfony/http-kernel/HttpKernel.php(76): Symfony\Component\HttpKernel\HttpKernel->handleRaw()
#5 /app/web/core/lib/Drupal/Core/StackMiddleware/Session.php(53): Symfony\Component\HttpKernel\HttpKernel->handle()

Steps to reproduce

Install the module, open path /index.phpauth

Maybe it depends on how the webserver is configured to rewrite rules, we are using a nginx setup.