chore: Add new line at the end of auth.php, login.php, and logout.php for consistency

auth.php

@@ -88,3 +88,4 @@ function logout() {
     }
     @session_destroy();
 }
+

login.php

@@ -284,3 +284,4 @@ $logoutMessage = isset($_GET['logout']) ? 'U bent succesvol en veilig uitgelogd.
     </script>
 </body>
 </html>
+

logout.php

@@ -7,3 +7,4 @@ require_once __DIR__ . '/auth.php';
 logout();
 header('Location: login.php?logout=1');
 exit;
+