Merge branch '5.0'

* 5.0:
  [Debug] fix ClassNotFoundFatalErrorHandler
  [FrameworkBundle] Document the router.cache_class_prefix parameter removal
  [Routing] Fix using a custom matcher & generator dumper class
  [Notifier] Add more specific types at documentation level when php engine can't
  [Serializer] Fix cache in MetadataAwareNameConverter
  [Dotenv] Fixed infinite loop with missing quote followed by quoted value
  [HttpClient] Added missing sprintf
  [TwigBridge] button_widget now has its title attr translated even if its label = null or false
  [PhpUnitBridge] When using phpenv + phpenv-composer plugin, composer executable is wrapped into a bash script
  [Messenger] Added check if json_encode succeeded
  [Messenger] Added check if json_encode succeeded
  [FrameworkBundle][ContainerLintCommand] Only skip .errored. services
  [HttpClient] fix exception in case of PSR17 discovery failure
  [DependencyInjection] Handle ServiceClosureArgument for callable in container linting
  fix processing chain adapter based cache pool
  [HttpKernel] release lock explicitly
  [Security] Prevent canceled remember-me cookie from being accepted
  [FrameworkBundle][TranslationUpdateCommand] Do not output positive feedback on stderr
  [Security\Guard] Fix missing typehints
  do not render preferred choices as selected

Author: nicolas-grekas

Message/SmsMessage.php

@@ -58,7 +58,7 @@ public function getPhone(): string
         return $this->phone;
     }
 
-    public function getRecipientId(): ?string
+    public function getRecipientId(): string
     {
         return $this->phone;
     }

Transport/NullTransportFactory.php

@@ -20,6 +20,9 @@
  */
 final class NullTransportFactory extends AbstractTransportFactory
 {
+    /**
+     * @return NullTransport
+     */
     public function create(Dsn $dsn): TransportInterface
     {
         if ('null' === $dsn->getScheme()) {