feature #1484 [make:auth] use getString() instead of get()

Co-authored-by: Simon André <smn.andre@gmail.com>

Author: seb-jean

src/Resources/skeleton/authenticator/LoginFormAuthenticator.tpl.php

@@ -16,15 +16,15 @@ public function __construct(private UrlGeneratorInterface $urlGenerator)
 
     public function authenticate(Request $request): Passport
     {
-        $<?= $username_field_var ?> = $request->getPayload()->get('<?= $username_field ?>', '');
+        $<?= $username_field_var ?> = $request->getPayload()->getString('<?= $username_field ?>');
 
         $request->getSession()->set(SecurityRequestAttributes::LAST_USERNAME, $<?= $username_field_var ?>);
 
         return new Passport(
             new UserBadge($<?= $username_field_var ?>),
-            new PasswordCredentials($request->getPayload()->get('password', '')),
+            new PasswordCredentials($request->getPayload()->getString('password')),
             [
-                new CsrfTokenBadge('authenticate', $request->getPayload()->get('_csrf_token')),<?= $remember_me_badge ? "
+                new CsrfTokenBadge('authenticate', $request->getPayload()->getString('_csrf_token')),<?= $remember_me_badge ? "
                 new RememberMeBadge(),\n" : "" ?>
             ]
         );