[php-src] Issue #15309: ReflectionClass can't detect readonly properties for mysqli

Issue: https://github.com/php/php-src/issues/15309 Author: RV7PR ### Description The following code: ```php <?php $reflection = new ReflectionClass(mysqli::class); $props = []; foreach ($reflection->getProperties() as $property) { $props[] = $property->getName() . ' | readonly: ' . (int) $property->isReadOnly(); } print_r($props); ``` Resulted in this output: ``` Array ( [0] => affected_rows | readonly: 0 [1] => client_info | readonly: 0 [2] => client_version | readonly: 0 [3] => connect_errno | readonly: 0 [4] => connect_error | readonly: 0 [5] => errno | readonly: 0 [6] => error | readonly: 0 [7] => error_list | readonly: 0 [8] => field_count | readonly: 0 [9] => host_info | readonly: 0 [10] => info | readonly: 0 [11] => insert_id | readonly: 0 [12] => server_info | readonly: 0 [13] => server_version | readonly: 0 [14] => sqlstate | readonly: 0 [15] => protocol_version | readonly: 0 [16] => thread_id | readonly: 0 [17] => warning_count | readonly: 0 ) ``` But I expected this output instead: ``` Array ( [0] => affected_rows | readonly: 1 [1] => client_info | readonly: 1 [2] => client_version | readonly: 1 [3] => connect_errno | readonly: 1 [4] => connect_error | readonly: 1 [5] => errno | readonly: 1 [6] => error | readonly: 1 [7] => error_list | readonly: 1 [8] => field_count | readonly: 1 [9] => host_info | readonly: 1 [10] => info | readonly: 1 [11] => insert_id | readonly: 1 [12] => server_info | readonly: 1 [13] => server_version | readonly: 1 [14] => sqlstate | readonly: 1 [15] => protocol_version | readonly: 1 [16] => thread_id | readonly: 1 [17] => warning_count | readonly: 1 ) ``` ### PHP Version PHP 8.3.8 ### Operating System _No response_