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/CommandLoader/CommandLoaderInterface.php

@@ -22,25 +22,21 @@ interface CommandLoaderInterface
     /**
      * Loads a command.
      *
-     * @param string $name
-     *
      * @return Command
      *
      * @throws CommandNotFoundException
      */
-    public function get($name);
+    public function get(string $name);
 
     /**
      * Checks if a command exists.
      *
-     * @param string $name
-     *
      * @return bool
      */
-    public function has($name);
+    public function has(string $name);
 
     /**
-     * @return string[] All registered command names
+     * @return string[]
      */
     public function getNames();
 }