[php-src] PR #22923: ext/session: report a rejected session cookie header

Pull Request: https://github.com/php/php-src/pull/22923 Author: iliaal php_session_send_cookie() dropped the result of sapi_add_header_ex() and always returned SUCCESS. When the SAPI refuses a Set-Cookie header containing CR or LF, the warning it emits can reach a userland error handler, and if that handler calls session_destroy() then php_session_reset_id() carries on and appends the released PS(id). Reproducer is a set_error_handler() that destroys the session, session_set_cookie_params(['path' => "/\r\nX: y"]), then session_start(): SIGSEGV on 8.4, 8.5 and master, under both CLI and CGI. php_session_reset_id() has handled a FAILURE from the cookie call since 8.4; it just never saw one.