Implement root step

[MAILPOET-4523]

mailpoet/lib/Automation/Engine/Control/RootStep.php

@@ -0,0 +1,20 @@
+<?php declare(strict_types = 1);
+
+namespace MailPoet\Automation\Engine\Control;
+
+use MailPoet\Automation\Engine\Workflows\Step;
+use MailPoet\Validator\Schema\ObjectSchema;
+
+class RootStep implements Step {
+  public function getKey(): string {
+    return 'core:root';
+  }
+
+  public function getName(): string {
+    return __('Root step', 'mailpoet');
+  }
+
+  public function getArgsSchema(): ObjectSchema {
+    return new ObjectSchema();
+  }
+}