[php-src] Issue #10951: Error "Cannot switch fibers" when creating a fiber in pcntl_signal

Issue: https://github.com/php/php-src/issues/10951 Author: Provoker ### Description Since version 8.2.0 when trying to create fiber in a function passed to pcntl_signal an "Cannot switch fibers in current execution context" error occurs. The documentation says only about limitation in the destructor. The following code: ```php <?php pcntl_signal(SIGINT, function () { $fiber = new Fiber(function () { Fiber::suspend('test'); }); var_dump($fiber->start()); }); posix_kill(getmypid(), SIGINT); pcntl_signal_dispatch(); ``` Resulted in this output: ``` string(4) "test" ``` But I expected this output instead: ``` Uncaught FiberError: Cannot switch fibers in current execution context ``` ### PHP Version PHP 8.2.0 ### Operating System _No response_