minor symfony#16333 [Console] Document AsCommand attribute (94noni)

This PR was squashed before being merged into the 5.4 branch.

Discussion
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[Console] Document AsCommand attribute

Replaces symfony#15123 as it seems stale
Close symfony#15003
Friendly ping `@OskarStark` for original PR review

Commits
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7a842f1 [Console] Document AsCommand attribute

Author: javiereguiluz

console.rst

@@ -151,6 +151,30 @@ with the ``console.command`` tag. If you're using the
 :ref:`default services.yaml configuration <service-container-services-load-example>`,
 this is already done for you, thanks to :ref:`autoconfiguration <services-autoconfigure>`.
 
+On PHP 8, you can use native attribute ``AsCommand`` to configure::
+
+    // src/Command/CreateUserCommand.php
+    namespace App\Command;
+
+    use Symfony\Component\Console\Attribute\AsCommand;
+    use Symfony\Component\Console\Command\Command;
+
+    #[AsCommand(
+        name: 'app:create-user',
+        description: 'Creates a new user.',
+        hidden: false,
+        aliases: ['app:add-user']
+    )]
+    class CreateUserCommand extends Command
+    {
+        // ...
+    }
+
+.. versionadded:: 5.3
+
+    The ability to use PHP attributes to configure commands was introduced in
+    Symfony 5.3.
+
 Executing the Command
 ---------------------