[php-src] Issue #9883: SplFileObject::__toString() reads next line

Issue: https://github.com/php/php-src/issues/9883 Author: cmb69 ### Description The following code: ```php <?php $file_stream = new SplFileObject(__FILE__, 'rb'); echo $file_stream; // line 4 echo $file_stream; // line 5 echo $file_stream; // line 6 echo $file_stream; // line 7 echo $file_stream; // line 8 echo $file_stream; // line 9 ``` Resulted in this output: ``` <?php $file_stream = new SplFileObject(__FILE__, 'rb'); echo $file_stream; // line 4 echo $file_stream; // line 5 ``` But I expected this output instead: ``` <?php <?php <?php <?php <?php <?php ``` See https://3v4l.org/gF4tm. The issue is due to the [erroneous fix](https://github.com/php/php-src/pull/3820) of [bug 77024](http://bugs.php.net/77024), where ::__toString() is now an alias of ::fgets() what appears to be strange. This issue has been discovered by @derickr. ### PHP Version PHP 8.0 ### Operating System any