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

plugins/php-imap/vendor/sebastian/diff/src/Exception/ConfigurationException.php

@@ -0,0 +1,38 @@
+<?php declare(strict_types=1);
+/*
+ * This file is part of sebastian/diff.
+ *
+ * (c) Sebastian Bergmann <sebastian@phpunit.de>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+namespace SebastianBergmann\Diff;
+
+use function get_class;
+use function gettype;
+use function is_object;
+use function sprintf;
+use Exception;
+
+final class ConfigurationException extends InvalidArgumentException
+{
+    public function __construct(
+        string $option,
+        string $expected,
+        $value,
+        int $code = 0,
+        ?Exception $previous = null
+    ) {
+        parent::__construct(
+            sprintf(
+                'Option "%s" must be %s, got "%s".',
+                $option,
+                $expected,
+                is_object($value) ? get_class($value) : (null === $value ? '<null>' : gettype($value) . '#' . $value)
+            ),
+            $code,
+            $previous
+        );
+    }
+}

plugins/php-imap/vendor/sebastian/diff/src/Exception/Exception.php

@@ -0,0 +1,16 @@
+<?php declare(strict_types=1);
+/*
+ * This file is part of sebastian/diff.
+ *
+ * (c) Sebastian Bergmann <sebastian@phpunit.de>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+namespace SebastianBergmann\Diff;
+
+use Throwable;
+
+interface Exception extends Throwable
+{
+}

plugins/php-imap/vendor/sebastian/diff/src/Exception/InvalidArgumentException.php

@@ -0,0 +1,14 @@
+<?php declare(strict_types=1);
+/*
+ * This file is part of sebastian/diff.
+ *
+ * (c) Sebastian Bergmann <sebastian@phpunit.de>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+namespace SebastianBergmann\Diff;
+
+class InvalidArgumentException extends \InvalidArgumentException implements Exception
+{
+}