- Symfony 6.4.*, API Platform 3.4 (resources converted to the new
  metadata with api:upgrade-resource), Twig 3.
- config/bootstrap.php: Dotenv(false) no longer means "no putenv" with
  Symfony 6: the env was not detected and .env.test.local not loaded, so
  the tests ran on the dev database. tests/bootstrap.php now refuses a
  database whose name does not contain "test".
- API responses unchanged (ApiTest compares them to a snapshot taken with
  the previous version): null values kept, read group on /api/public/poi/all.
- NelmioApiDocBundle removed: /api/doc and /api/doc.json redirect to the
  API Platform documentation (/api/docs).
- gamez/ramsey-uuid-normalizer (abandoned) ported in App\Serializer.
- sonata-project/classification-bundle kept on 4.4 (later versions need
  a newer Sonata Admin).
- Twig 3: spaceless tag, for ... if, blocks under if (Twig 2 ignored these
  conditions: same output kept), Twig_* classes.
- Container: ContainerInterface bound to service_container, token storage
  injected in the admins, AbstractController::get() removed.
- Session storage factory, RoutingConfigurator, new handler signatures.