Remove the vendor directory in .gitignore as these dependencies are needed for php-imap

plugins/php-imap/vendor/symfony/polyfill-php83/Resources/stubs/DateException.php

@@ -0,0 +1,16 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+if (\PHP_VERSION_ID < 80300) {
+    class DateException extends Exception
+    {
+    }
+}