Description:
------------
Prior to PHP 8.1 to invoke private method with ReflectionMethod calling "setAccessible" with "true" was needed.

Test script:
---------------
<?php

class Foo {
    private function bar() { return 42; }
}

$foo = new Foo();

$reflection = new \ReflectionMethod($foo, 'bar');

echo $reflection->invoke($foo);

Expected result:
----------------
The need of calling "setAccessible": "$reflection->setAccessible(true);".