Fix assign cache 'this' context

[BesedinSasha]

This PR resolves bug with '$this' context. For some reason after getting closure from static cacheAssign variable and calling accessor, $this context doesn't change. I assumed that reson is using $this in closure instead of $instance

Part of proxy class code from callInitializer method

private function callInitializer0dc81($methodName, array $parameters)
    {
// hidden lines of code
        static $cacheAssignFoo;

        $cacheAssignFoo ?? $cacheAssignFoo = \Closure::bind(function ($instance, $nonReferenceableProperties) { // $instance is not using anywhere
            isset($nonReferenceableProperties->id_on_Foo) && $this->id = $nonReferenceableProperties->id_on_Foo;
            isset($nonReferenceableProperties->name_on_Foo) && $this->name = $nonReferenceableProperties->name_on_Foo;
        }, $this, 'Foo');

        $cacheAssignFoo($this, $nonReferenceableProperties); // after calling cached closure we have $this context without $id and $name properties

// hidden lines of code
}

Code that reproduces this bug:

<?php

declare(strict_types=1);

use ProxyManager\Factory\LazyLoadingGhostFactory;
use ProxyManager\Proxy\GhostObjectInterface;

require_once 'vendor/autoload.php';

class Foo
{
    private int $id;

    private string $name;

    public function __construct(int $id, string $name)
    {
        $this->id = $id;

        $this->name = $name;
    }

    public function getIt(): int
    {
        return $this->id;
    }

    public function setId(int $id): void
    {
        $this->id = $id;
    }

    public function getName(): string
    {
        return $this->name;
    }

    public function setName(string $name): void
    {
        $this->name = $name;
    }
}

$proxyFactory = new LazyLoadingGhostFactory();

function createInitializer(int $num)
{
    return function (
        GhostObjectInterface|Foo $proxy,
        string $method,
        array $parameters,
        ?Closure &$initializer,
        array $properties
    ) use ($num) {
        $initializer = null;

        $properties["\0".Foo::class."\0".'id'] = $num;
        $properties["\0".Foo::class."\0".'name'] = "Name_$num";

        return true;
    };
}

$foo1 = $proxyFactory->createProxy(Foo::class, createInitializer(1));

echo $foo1->getName().PHP_EOL;

$foo2 = $proxyFactory->createProxy(Foo::class, createInitializer(2));

echo $foo2->getName().PHP_EOL; // Fatal error: Uncaught Error: Cannot access uninitialized non-nullable property Foo::$name

[nicolas-grekas]

Good catch thanks.

[BesedinSasha]

@nicolas-grekas 👍