Error „should return static(Test) but returns Test“

```php
class Test
{
	/** @return static */
	function do()
	{
		return $this->do()->do();
	}
}
```

This generates error Method Test::do() should return static(Test) but returns Test.

https://phpstan.org/r/6307080e-727f-4a61-a816-f3e355ab9fc4