feature #968 [make:entity] APIP: use new attribute if exists (nikophil)

This PR was merged into the 1.0-dev branch.

Discussion
----------

[make:entity] APIP: use new attribute if exists

Hi,

here is an update to use new `ApiResource` attribute from api platofrm v3 when providing `--api-resource` flag in `make:entity` command.

This cannot be tested yet since v3 is not released

Commits
-------

f2a778a APIP: use new attribute if exists

Author: weaverryan

src/Resources/skeleton/doctrine/Entity.tpl.php

@@ -2,7 +2,8 @@
 
 namespace <?= $namespace ?>;
 
-<?php if ($api_resource): ?>use ApiPlatform\Core\Annotation\ApiResource;
+<?php if ($api_resource && class_exists(\ApiPlatform\Metadata\ApiResource::class)): ?>use ApiPlatform\Metadata\ApiResource;
+<?php elseif ($api_resource): ?>use ApiPlatform\Core\Annotation\ApiResource;
 <?php endif ?>
 use <?= $repository_full_class_name ?>;
 use Doctrine\ORM\Mapping as ORM;