migration symfony 5 4 (#300)

* symfony 5.4 (diff dev)

* symfony 5.4 (working)

* symfony 5.4 (update autoload)

* symfony 5.4 (remove swiftmailer mailer implementation)

* symfony 5.4 (php doc and split Global accessor class)


### Impacted packages:

composer require php:">=7.2.5 <8.0.0" symfony/console:5.4.* symfony/dotenv:5.4.* symfony/framework-bundle:5.4.* symfony/twig-bundle:5.4.* symfony/yaml:5.4.* --update-with-dependencies

composer require symfony/stopwatch:5.4.* symfony/web-profiler-bundle:5.4.* --dev --update-with-dependencies

lib/symfony/console/Tester/Constraint/CommandIsSuccessful.php

@@ -0,0 +1,55 @@
+<?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\Console\Tester\Constraint;
+
+use PHPUnit\Framework\Constraint\Constraint;
+use Symfony\Component\Console\Command\Command;
+
+final class CommandIsSuccessful extends Constraint
+{
+    /**
+     * {@inheritdoc}
+     */
+    public function toString(): string
+    {
+        return 'is successful';
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function matches($other): bool
+    {
+        return Command::SUCCESS === $other;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function failureDescription($other): string
+    {
+        return 'the command '.$this->toString();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function additionalFailureDescription($other): string
+    {
+        $mapping = [
+            Command::FAILURE => 'Command failed.',
+            Command::INVALID => 'Command was invalid.',
+        ];
+
+        return $mapping[$other] ?? sprintf('Command returned exit status %d.', $other);
+    }
+}