Import latest app updates from streamline

An updated set of source files and initialization was provided by streamline to
address issues observed during initial testing. These files have been updated in
order to generate a new set of app images.

docker/streamline-src/vendor/symfony/mailer/Event/MessageEvents.php

@@ -1,74 +0,0 @@
-<?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.
- */
-
-namespace Symfony\Component\Mailer\Event;
-
-use Symfony\Component\Mime\RawMessage;
-
-/**
- * @author Fabien Potencier <fabien@symfony.com>
- */
-class MessageEvents
-{
-    /**
-     * @var MessageEvent[]
-     */
-    private array $events = [];
-
-    /**
-     * @var array<string, bool>
-     */
-    private array $transports = [];
-
-    public function add(MessageEvent $event): void
-    {
-        $this->events[] = $event;
-        $this->transports[$event->getTransport()] = true;
-    }
-
-    public function getTransports(): array
-    {
-        return array_keys($this->transports);
-    }
-
-    /**
-     * @return MessageEvent[]
-     */
-    public function getEvents(?string $name = null): array
-    {
-        if (null === $name) {
-            return $this->events;
-        }
-
-        $events = [];
-        foreach ($this->events as $event) {
-            if ($name === $event->getTransport()) {
-                $events[] = $event;
-            }
-        }
-
-        return $events;
-    }
-
-    /**
-     * @return RawMessage[]
-     */
-    public function getMessages(?string $name = null): array
-    {
-        $events = $this->getEvents($name);
-        $messages = [];
-        foreach ($events as $event) {
-            $messages[] = $event->getMessage();
-        }
-
-        return $messages;
-    }
-}