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

plugins/php-imap/vendor/illuminate/contracts/Support/Responsable.php

@@ -0,0 +1,14 @@
+<?php
+
+namespace Illuminate\Contracts\Support;
+
+interface Responsable
+{
+    /**
+     * Create an HTTP response that represents the object.
+     *
+     * @param  \Illuminate\Http\Request  $request
+     * @return \Symfony\Component\HttpFoundation\Response
+     */
+    public function toResponse($request);
+}