minor #16690 [Messenger] Services that need reset must implement ResetInterface (volendavidov)

This PR was squashed before being merged into the 6.1 branch.

Discussion
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[Messenger] Services that need reset must implement ResetInterface

Closes #16688

Commits
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0203dfb [Messenger] Services that need reset must implement ResetInterface

Author: javiereguiluz

messenger.rst

@@ -707,11 +707,16 @@ you can decide to not take care of services that may leak memory.
 
 On the other hand, workers usually sequentially process messages in long-running CLI processes, which don't
 finish after processing a single message. That's why you must be careful about service
-states to prevent information and/or memory leakage.
+states to prevent information and/or memory leakage as Symfony will inject the same instance of a
+service, preserving the internal state of the service between messages.
 
 However, certain Symfony services, such as the Monolog
 :ref:`fingers crossed handler <logging-handler-fingers_crossed>`, leak by design.
 That's why Symfony automatically resets the service container between two messages.
+If a service is not stateless and you want to reset its properties after each message, then
+the service must implement :class:`Symfony\\Contracts\\Service\\ResetInterface` where you can reset the
+properties in the ``reset()`` method.
+
 If you don't want to reset the container, add the ``--no-reset`` option when
 running the ``messenger:consume`` command.