Merge branch '6.4' into 7.0

* 6.4:
  fix compatibility with Redis Relay 0.8.1
  use more entropy with uniqid()
  [Cache] Improve `dbindex` DSN parameter parsing
  Support for PHP-CS-Fixer's parallel runner
  use more entropy with uniqid()
  [Contracts][HttpClient] Skip tests when zlib's `ob_gzhandler()` doesn't exist

Tests/Matcher/Dumper/CompiledUrlMatcherDumperTest.php

@@ -30,7 +30,7 @@ protected function setUp(): void
     {
         parent::setUp();
 
-        $this->dumpPath = sys_get_temp_dir().\DIRECTORY_SEPARATOR.'php_matcher.'.uniqid('CompiledUrlMatcher').'.php';
+        $this->dumpPath = sys_get_temp_dir().\DIRECTORY_SEPARATOR.'php_matcher.'.uniqid('CompiledUrlMatcher', true).'.php';
     }
 
     protected function tearDown(): void