minor #13582 Remove old AppBundle code from XML service definition example (7ochem)

This PR was merged into the 4.4 branch.

Discussion
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Remove old AppBundle code from XML service definition example

In the XML example of the default service definition, there still was the AppBundle prototype definition from the 3.4 docs, besides the new App definition. I made the XML example resemble the YAML example.

Commits
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2bf0473 Remove old AppBundle code from XML service definition example

Author: javiereguiluz

service_container.rst

@@ -176,12 +176,12 @@ each time you ask for it.
                     <!-- Default configuration for services in *this* file -->
                     <defaults autowire="true" autoconfigure="true"/>
 
+                    <!-- makes classes in src/ available to be used as services -->
+                    <!-- this creates a service per class whose id is the fully-qualified class name -->
                     <prototype namespace="App\" resource="../src/*" exclude="../src/{DependencyInjection,Entity,Migrations,Tests,Kernel.php}"/>
 
-                    <!-- makes classes in src/AppBundle available to be used as services -->
-                    <prototype namespace="AppBundle\"
-                        resource="../../src/AppBundle/*"
-                        exclude="../../src/AppBundle/{Entity,Repository}"/>
+                    <!-- ... -->
+
                 </services>
             </container>