minor #13602 Fix link to ServiceSubscriberInterface (jspaetzel)

This PR was merged into the 5.0 branch.

Discussion
----------

Fix link to ServiceSubscriberInterface

<!--

If your pull request fixes a BUG, use the oldest maintained branch that contains
the bug (see https://symfony.com/roadmap for the list of maintained branches).

If your pull request documents a NEW FEATURE, use the same Symfony branch where
the feature was introduced (and `master` for features of unreleased versions).

-->

Commits
-------

4dc8668 Fix link to ServiceSubscriberInterface

Author: javiereguiluz

service_container/service_subscribers_locators.rst

@@ -65,7 +65,7 @@ through a **Service Locator**, a separate lazy-loaded container.
 Defining a Service Subscriber
 -----------------------------
 
-First, turn ``CommandBus`` into an implementation of :class:`Symfony\\Component\\DependencyInjection\\ServiceSubscriberInterface`.
+First, turn ``CommandBus`` into an implementation of :class:`Symfony\\Contracts\\Service\\ServiceSubscriberInterface`.
 Use its ``getSubscribedServices()`` method to include as many services as needed
 in the service subscriber and change the type hint of the container to
 a PSR-11 ``ContainerInterface``::