Merge branch '6.4' into 7.0

* 6.4:
  replace wurstmeister Docker images for Kafka and Zookeeper
  [PasswordHasher] Make bcrypt nul byte hash test tolerant to PHP related failures
  [HttpClient] Revert fixing curl default options
  [VarExporter] fix proxy helper when a method returns null
  [Validator] Update Dutch (nl) translation
  Fix exception thrown during `LDAP_MODIFY_BATCH_REMOVE_ALL` batch operations
  Fix various warnings across components test suite

Response/CurlResponse.php

@@ -177,6 +177,10 @@ public function __construct(CurlClientState $multi, \CurlHandle|string $ch, ?arr
             curl_multi_remove_handle($multi->handle, $ch);
             curl_setopt_array($ch, [
                 \CURLOPT_NOPROGRESS => true,
+                \CURLOPT_PROGRESSFUNCTION => null,
+                \CURLOPT_HEADERFUNCTION => null,
+                \CURLOPT_WRITEFUNCTION => null,
+                \CURLOPT_READFUNCTION => null,
                 \CURLOPT_INFILE => null,
             ]);