[php-src] Issue #9388: Read of unset typed property /w magic __get throws wrong message

Issue: https://github.com/php/php-src/issues/9388 Author: mvorisek ### Description demo: https://3v4l.org/P7jXD (/wo return at all) demo 2: https://3v4l.org/6RlfS (/w incompatible return type) demo 3: https://3v4l.org/O9prE (/w type that can be implicitly casted, but not when using strict types) The error message Cannot assign null to property Cl::$name of type string is wrong & hard to understand, as there is no assignment anywhere. demo 4: https://3v4l.org/PaD9b (/w same return type as typed property, nothing wrong here, but it shows nothing is assigned as the error message claims) ### PHP Version 8.0+ ### Operating System any