bug #4641 Add missing autoload include in basic console application example (senkal)

This PR was merged into the 2.3 branch.

Discussion
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Add  missing autoload include in basic console application example

| Q                      | A
| ------------------- | ---
| Doc fix?           | [yes]
| New doc          | [no]
| Applies to           | all
| Fixed tick         |

Commits
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f6fac50 Fix for symfony code standards
6f56270 Add  missing autoload include in basic application example

Author: weaverryan

components/console/introduction.rst

@@ -88,6 +88,8 @@ an ``Application`` and adds commands to it::
     <?php
     // application.php
 
+    require __DIR__.'/vendor/autoload.php';
+
     use Acme\Console\Command\GreetCommand;
     use Symfony\Component\Console\Application;