[php-src] Issue #8099: ALERT: oops, unknown child (145) exited with code 0

Issue: https://github.com/php/php-src/issues/8099 Author: ammytech-acquia ### Description The following code: ```php <?php .... child = fpm_child_find(pid); ... if (child) { struct fpm_worker_pool_s *wp = child->wp; .... } else { zlog(ZLOG_ALERT, "oops, unknown child (%d) exited %s. Please open a bug report (https://bugs.php.net).", pid, buf); } ``` Resulted in this output: ``` we have below configuration in php-fpm.conf and pool fpm process.max = 5 pm = ondemand pm.max_children = 1000 pm.start_servers = 1 pm.min_spare_servers = 1 pm.max_spare_servers = 2 pm.process_idle_timeout = 10s pm.max_requests = 500 pm.child_memory = 256 pm.spare_memory = 320 ``` But I expected this output instead: ``` child = fpm_child_find(pid); child must be found as we have set configuration accordingly ``` ### PHP Version PHP 7.4.26 ### Operating System Ubuntu 16.04.7 LTS (Xenial Xerus)