Creating array property in SessionSection has no effect

[thorewi]

Version: 3.1.0

Bug Description

When I create sessionSection and save an array property to it with one element, it does not have any effect.

Steps To Reproduce

$cart = $this->session->getSection('cart');			
$cart->items[0] = 0;
echo $cart->items[0];

I get notice Trying to access array offset on value of type null.

Expected Behavior

To get 0

[redeyecz]

There is a typo in Nette\Http\SessionSection, missing reference in __get

	/**
	 * Gets a variable from this session section.
	 * @return mixed
	 */
	public function &__get(string $name)
	{
		$data = &$this->getData(false); // <=== this line is missing the reference in version v3.1.0
		if ($this->warnOnUndefined && !array_key_exists($name, $data ?? [])) {
			trigger_error("The variable '$name' does not exist in session section");
		}

		return $data[$name];
	}