adds .gcloudignore to wordpress copy (GoogleCloudPlatform#710)

Author: bshaffer

appengine/php72/wordpress/wordpress.php

@@ -98,6 +98,7 @@
 
         // copy all the sample files into the project dir and replace parameters
         $wordpress->copyFiles(__DIR__ . '/files', [
+            '.gcloudignore' => '/',
             'app.yaml' => '/',
             'cron.yaml' => '/',
             'php.ini' => '/',