minor #9545 Add kernel to list of excluded registered services (michaelperrin)

This PR was merged into the 4.0 branch.

Discussion
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Add kernel to list of excluded registered services

Doc change following this PR: symfony/recipes#355

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8e3b473 Add kernel to list of excluded registered services

Author: javiereguiluz

service_container.rst

@@ -148,7 +148,7 @@ each time you ask for it.
                 # this creates a service per class whose id is the fully-qualified class name
                 App\:
                     resource: '../src/*'
-                    exclude: '../src/{Entity,Migrations,Tests}'
+                    exclude: '../src/{Entity,Migrations,Tests,Kernel.php}'
 
                 # ...