Don't register handlers unless enabled

Problem/Motivation

Following the #3609101: Recreating a trashed redirect inside a workspace fails with a duplicate hash database error fix, the following exception is thrown when used on a site with domain's domain_config_ui submodule enabled:

Symfony\Component\DependencyInjection\Exception\ServiceCircularReferenceException: Circular reference detected for service "router.route_provider", path: "options_request_listener -> router.route_provider -> path_processor_manager -> path_alias.path_processor -> path_alias.manager -> path_alias.repository -> trash.manager -> Drupal\trash\Hook\TrashHandler\RedirectTrashHandler -> redirect.repository -> router -> router.no_access_checks". in Drupal\Component\DependencyInjection\Container->get() (line 148 of core/lib/Drupal/Component/DependencyInjection/Container.php). 

This happens because Trash handler services are registered even when they're not enabled.

It seems that running Drupal 11.4 avoids the circular reference crash due to #3571046: Use tagged iterators in PathProcessorManager and RouteProcessorManager since that lazy loads the services.

Steps to reproduce

1. On Drupal 11.3, have the following modules installed: Trash, Redirect and Domain Config UI.
2. Enable Trash on Path Alias and Node types.
3. Viewing certain admin page or making an AJAX request (e.g. delete) should trigger the exception.

Proposed resolution

Lazy load the redirect repository so that Trash doesn't have to wrestle with service dependency issues.

Remaining tasks

Provide MR.

User interface changes

N/A

API changes

N/A

Data model changes

N/A