[php-src] Issue #9551: File descriptors / some procfs entries not openable by php

Issue: https://github.com/php/php-src/issues/9551 Author: SpencerMalone ### Description The following code: ```php <?php file_put_contents("/proc/1/fd/1", "hi"); ``` Resulted in this output: ``` file_put_contents(/proc/1/fd/1): failed to open stream: No such file or directory ``` But I expected this output instead: ``` 2 ``` This is highly impactful for containerized PHP environments. php-fpm has unique workarounds that they've utilized, and in the past the fd stream wrapper was implemented to support managing the current process's file descriptors, but if you are in a different SAPI and/or utilize forking or execing to other PHP scripts, stdout in a docker container quickly turns into a black hole in terms of container logging, where it's expected that all logs are sent to the PID 1 stdout/err. ### PHP Version 7.4 ### Operating System Centos 7.9