minor #7026 Added information about injecting a logger to a service (hiddewie, javiereguiluz)

This PR was merged into the 2.7 branch.

Discussion
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Added information about injecting a logger to a service

Issue #7011.

I've added a small piece about injecting a logger to a service. However, the separate page about processors seems quite clear to me, also about the DI tags.

Commits
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a500ff3 Proposed a minor reword
c8992e6 Added information about injecting a logger to your service

Author: xabbuh

logging.rst

@@ -308,6 +308,15 @@ option of your handler to ``rotating_file``:
             ),
         ));
 
+Using a Logger inside a Service
+-------------------------------
+
+To use a logger in your own services, add the ``@logger`` service as an argument
+of those services. If you want to use a pre-configured logger which uses a
+specific channel (``app`` by default), use the ``monolog.logger`` tag  with the
+``channel`` property as explained in the
+:ref:`Dependency Injection reference <dic_tags-monolog>`.
+
 Adding extra Data to each Log (e.g. a unique request token)
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