Merge branch '5.1'

* 5.1:
  Enable "native_constant_invocation" CS rule
  Make AbstractPhpFileCacheWarmer public
  Fix CS
  Add a warning comment on ldap empty password
  Bump Symfony version to 4.4.14
  Update VERSION for 4.4.13
  Update CHANGELOG for 4.4.13
  [PhpunitBridge] Fix deprecation type detection

Author: nicolas-grekas

function.php

@@ -22,6 +22,6 @@
      */
     function trigger_deprecation(string $package, string $version, string $message, ...$args): void
     {
-        @trigger_error(($package || $version ? "Since $package $version: " : '').($args ? vsprintf($message, $args) : $message), E_USER_DEPRECATED);
+        @trigger_error(($package || $version ? "Since $package $version: " : '').($args ? vsprintf($message, $args) : $message), \E_USER_DEPRECATED);
     }
 }