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

plugins/php-imap/vendor/illuminate/contracts/Broadcasting/ShouldBroadcast.php

@@ -0,0 +1,13 @@
+<?php
+
+namespace Illuminate\Contracts\Broadcasting;
+
+interface ShouldBroadcast
+{
+    /**
+     * Get the channels the event should broadcast on.
+     *
+     * @return \Illuminate\Broadcasting\Channel|\Illuminate\Broadcasting\Channel[]|string[]|string
+     */
+    public function broadcastOn();
+}