[php-src] Issue #19187: PHP 8.4: `PropertyReflector::getSettableType` includes "?" in nullable identifier names.

Issue: https://github.com/php/php-src/issues/19187 Author: BusterNeece ### Description It appears that the type name returned by ReflectionProperty::getSettableType() will include the nullable question mark in the case of nullable values (i.e. ?string for string|null). This is inconsistent with existing behavior and the return type of ReflectionProperty::getType() given the same type hint. The following code: ```php <?php class Foo { public string|null $bar { set (string|null $value) => $value ?? 'default'; } } $reflProp = new ReflectionProperty(Foo::class, 'bar'); echo $reflProp->getType()->getName(); echo $reflProp->getSettableType()->getName(); ``` Resulted in this output: ``` string ?string ``` But I expected this output instead: ``` string string ``` ### PHP Version ```plain PHP 8.4.10 (cli) (built: Jul 3 2025 22:57:54) (NTS) Copyright (c) The PHP Group Built by https://github.com/docker-library/php Zend Engine v4.4.10, Copyright (c) Zend Technologies with Zend OPcache v8.4.10, Copyright (c), by Zend Technologies with Xdebug v3.4.4, Copyright (c) 2002-2025, by Derick Rethans ``` ### Operating System Debian Bookworm