Merge branch '5.4' into 6.0

* 5.4:
  [Runtime] Consider also $_ENV when resolving APP_RUNTIME and APP_RUNTIME_OPTIONS
  [WebProfilerBundle] Add a "previews tab in mailer profiler for HTML email
  [Config] Fix signature generation with nested attributes on PHP 8.1
  [Cache] allow/provide psr/simple-cache v2
  [Validator] Add missing translations for Slovenian (sl)
  Add missing translations for Bosnian (bs)
  Bump Symfony version to 4.4.34
  Update VERSION for 4.4.33
  Update CONTRIBUTORS for 4.4.33
  Update CHANGELOG for 4.4.33

Author: nicolas-grekas

DataCollector/MessageDataCollector.php

@@ -42,6 +42,14 @@ public function getEvents(): MessageEvents
         return $this->data['events'];
     }
 
+    /**
+     * @internal
+     */
+    public function base64Encode(string $data): string
+    {
+        return base64_encode($data);
+    }
+
     /**
      * {@inheritdoc}
      */