feature #578 Move login route to const (JakubSzczesniak)

This PR was merged into the 1.0-dev branch.

Discussion
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Move login route to const

To eliminate long debug time and bug fixing in case of change login route.  Connected with symfony/symfony-docs#13363

Commits
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9ce6179 Move login route to const

Author: weaverryan

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

@@ -24,6 +24,8 @@ class <?= $class_name; ?> extends AbstractFormLoginAuthenticator<?= $password_au
 {
     use TargetPathTrait;
 
+    public const LOGIN_ROUTE = 'app_login';
+
 <?= $user_is_entity ? "    private \$entityManager;\n" : null ?>
     private $urlGenerator;
     private $csrfTokenManager;
@@ -39,7 +41,7 @@ public function __construct(<?= $user_is_entity ? 'EntityManagerInterface $entit
 
     public function supports(Request $request)
     {
-        return 'app_login' === $request->attributes->get('_route')
+        return self::LOGIN_ROUTE === $request->attributes->get('_route')
             && $request->isMethod('POST');
     }
 
@@ -108,6 +110,6 @@ public function onAuthenticationSuccess(Request $request, TokenInterface $token,
 
     protected function getLoginUrl()
     {
-        return $this->urlGenerator->generate('app_login');
+        return $this->urlGenerator->generate(self::LOGIN_ROUTE);
     }
 }