minor #9554 Remove faulty PHP code blocks (stof)

This PR was merged into the 3.4 branch.

Discussion
----------

Remove faulty PHP code blocks

The `_instanceof` and `_defaults` APIs have not equivalent for the low-level Definition API, as they are resource-scoped features and the low-level API does not have any concept of resource doing the definition.

`registerForAutoconfiguration` is totally unrelated to `_instanceof`. It is the partner of the ` autoconfigure` API.

A valid replacement could be to use the new PHP DSL (which has equivalent features), but I don't think it is used anywhere in the DI documentation yet. And using it would require a policy about how to distinguish code blocks using the PHP DSL in a config file, and code blocks using the lower-level PHP API. So I kept this out of this PR, by only removing wrong doc.

Commits
-------

cbcbb43 Remove faulty PHP code blocks

Author: javiereguiluz

service_container/3.3-di-changes.rst

@@ -87,32 +87,6 @@ Symfony Standard Edition:
             </services>
         </container>
 
-    .. code-block:: php
-
-        // app/config/services.php
-        use Symfony\Component\DependencyInjection\Definition;
-
-        // To use as default template
-        $definition = new Definition();
-
-        $definition
-            ->setAutowired(true)
-            ->setAutoconfigured(true)
-            ->setPublic(false)
-        ;
-
-        $this->registerClasses($definition, 'AppBundle\\', '../../src/AppBundle/*', '../../src/AppBundle/{Entity,Repository}');
-
-        // Changes default config
-        $definition
-            ->addTag('controller.service_arguments')
-        ;
-
-        // $this is a reference to the current loader
-        $this->registerClasses($definition, 'AppBundle\\Controller\\', '../../src/AppBundle/Controller/*');
-
-        // add more services, or override services that need manual wiring
-
 This small bit of configuration contains a paradigm shift of how services
 are configured in Symfony.
 
@@ -160,22 +134,6 @@ thanks to the following config:
             </services>
         </container>
 
-    .. code-block:: php
-
-        // app/config/services.php
-        use Symfony\Component\DependencyInjection\Definition;
-
-        // To use as default template
-        $definition = new Definition();
-
-        $definition
-            ->setAutowired(true)
-            ->setAutoconfigured(true)
-            ->setPublic(false)
-        ;
-
-        $this->registerClasses($definition, 'AppBundle\\', '../../src/AppBundle/*', '../../src/AppBundle/{Entity,Repository}');
-
 This means that every class in ``src/AppBundle/`` is *available* to be used as a
 service. And thanks to the ``_defaults`` section at the top of the file, all of
 these services are **autowired** and **private** (i.e. ``public: false``).
@@ -512,18 +470,6 @@ inherited from an abstract definition:
             </services>
         </container>
 
-    .. code-block:: php
-
-        // app/config/services.php
-        use AppBundle\Domain\LoaderInterface;
-
-        // ...
-
-        /* This method returns a child definition to define the default
-           configuration of the given class or interface */
-        $container->registerForAutoconfiguration(LoaderInterface::class)
-            ->addTag('app.domain_loader');
-
 What about Performance
 ----------------------