Merge branch '3.4' into 4.4

* 3.4:
  Fix versions
  [Security/Http] Allow setting cookie security settings for delete_cookies
  [FrameworkBundle] revert to legacy wiring of the session when circular refs are detected
  bumped Symfony version to 3.4.40
  updated VERSION for 3.4.39
  update CONTRIBUTORS for 3.4.39
  updated CHANGELOG for 3.4.39
  update Italian translation
  [Validator] Add missing Hungarian translations
  [Validator] Add the missing translations for the Arabic (ar) locale
  [Validator] Add missing vietnamese translations
  [Console] Fix OutputStream for PHP 7.4
  add German translations
  bug #36157 [Validator] Assert Valid with many groups
  [Validator] Add missing Lithuanian translations
  Fixed some typos
  Add french "at least" constraint translations

Author: nicolas-grekas

Tests/RouteCollectionBuilderTest.php

@@ -256,7 +256,7 @@ public function providePrefixTests()
         // shows that a prefix will always be given the starting slash
         $tests[] = ['0', '/foo', '/0/foo'];
 
-        // spaces are ok, and double slahses at the end are cleaned
+        // spaces are ok, and double slashes at the end are cleaned
         $tests[] = ['/ /', '/foo', '/ /foo'];
 
         return $tests;