Merge branch '6.0' into 6.1

* 6.0:
  Use mb_convert_encoding instead of utf8_decode
  [SecurityBundle] Remove forgotten unused code
  Minor @requires function tests cleanup
  [FrameworkBundle] Always add CacheCollectorPass
  Fix "Notice: Undefined index: headers" in messenger with Oracle
  [String] Fix ansi escape sequences regex
  Indicate support for doctrine/persistence 3
  [Routing] fix router base url when default uri has trailing slash
  Replace deprecated String.prototype.substr()

Author: derrabus

Tests/MarkingStore/MethodMarkingStoreTest.php

@@ -87,9 +87,6 @@ public function testGetMarkingWithValueObject()
         $this->assertSame('first_place', (string) $subject->getMarking());
     }
 
-    /**
-     * @requires PHP 7.4
-     */
     public function testGetMarkingWithUninitializedProperty()
     {
         $subject = new SubjectWithType();
@@ -102,9 +99,6 @@ public function testGetMarkingWithUninitializedProperty()
         $this->assertCount(0, $marking->getPlaces());
     }
 
-    /**
-     * @requires PHP 7.4
-     */
     public function testGetMarkingWithUninitializedProperty2()
     {
         $subject = new SubjectWithType();