Fixing depreceated HttpKernel\DependencyInjection\Extension class which is now considered internal

[lucasfoussier]

With the latest Symfony versions(7.1) , we have some depreceated reported in logs :

The "Symfony\Component\HttpKernel\DependencyInjection\Extension" class is considered internal since Symfony 7.1, to be deprecated in 8.1; use Symfony\Component\DependencyInjection\Extension\Extension instead. It may change without further notice. You should not use it from "Nzo\UrlEncryptorBundle\DependencyInjection\NzoEncryptorExtension".

To fix this, change the import in the file Nzo\UrlEncryptorBundle\DependencyInjection\NzoEncryptorExtension as suggested fix the issues.

As described in the composer.json the bundle support the version starting with symfony version > 4.4 (^4.4|^5.0|^6.0|^7.0).
The suggested class used in this PR was already available in 4.4 as you can see here : https://github.com/symfony/symfony/blob/4.4/src/Symfony/Component/DependencyInjection/Extension/Extension.php so it should be harmless for all the users of the bundle.

[nayzo]

Thanks @lucasfoussier