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

plugins/php-imap/vendor/nesbot/carbon/src/Carbon/CarbonConverterInterface.php

@@ -0,0 +1,21 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * This file is part of the Carbon package.
+ *
+ * (c) Brian Nesbitt <brian@nesbot.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Carbon;
+
+use DateTimeInterface;
+
+interface CarbonConverterInterface
+{
+    public function convertDate(DateTimeInterface $dateTime, bool $negated = false): CarbonInterface;
+}