minor symfony#9372 Update dependency_injection.rst (flip111)

This PR was submitted for the 4.0 branch but it was merged into the 2.7 branch instead (closes symfony#9372).

Discussion
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Update dependency_injection.rst

typo in class name

Commits
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b902489 Update dependency_injection.rst

Author: javiereguiluz

create_framework/dependency_injection.rst

@@ -183,7 +183,7 @@ Now, here is how you can register a custom listener in the front controller::
     // ...
     use Simplex\StringResponseListener;
 
-    $container->register('listener.string_response', StringResposeListener::class);
+    $container->register('listener.string_response', StringResponseListener::class);
     $container->getDefinition('dispatcher')
         ->addMethodCall('addSubscriber', array(new Reference('listener.string_response')))
     ;