[PWA-1139] [MAGENTO CLOUD] PWA causing Fastly pages not cached (UPWARD-PHP) (#6)

* Add placeholder plugin to work around compile bug

* Add a docblock to class

Author: tjwiebell

Plugin/Magento/Framework/App/DICompileFix.php

@@ -0,0 +1,16 @@
+<?php
+/**
+ *
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+
+declare(strict_types=1);
+
+namespace Magento\UpwardConnector\Plugin\Magento\Framework\App;
+
+/**
+ * Empty class plugin to work around MC-39132. Prevents AppendNoStoreCacheHeader
+ * plugin from leaking into the pwa area.
+ */
+class DICompileFix {}

etc/pwa/di.xml

@@ -8,4 +8,7 @@
 <config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
     <preference for="Magento\Framework\App\FrontControllerInterface" type="Magento\UpwardConnector\Controller\Upward" />
+    <type name="Magento\Framework\App\FrontControllerInterface">
+        <plugin name="di_compile_fix" type="Magento\UpwardConnector\Plugin\Magento\Framework\App\DICompileFix" />
+    </type>
 </config>