Move from phpat-example

Signed-off-by: Oliver Davies <oliver@oliverdavies.uk>

php/phpat/src/Action/DoesSomething.php

@@ -0,0 +1,13 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Action;
+
+readonly final class DoesSomething
+{
+    public function __invoke(): void
+    {
+        var_dump('Doing something...');
+    }
+}