ext/ftp: Change return type of ftp_set_option() to true

It either returns true or throws an Error

Author: Girgias

ext/ftp/ftp.stub.php

@@ -132,7 +132,7 @@ function ftp_close(FTP\Connection $ftp): bool {}
     function ftp_quit(FTP\Connection $ftp): bool {}
 
     /** @param int|bool $value */
-    function ftp_set_option(FTP\Connection $ftp, int $option, $value): bool {}
+    function ftp_set_option(FTP\Connection $ftp, int $option, $value): true {}
     function ftp_get_option(FTP\Connection $ftp, int $option): int|bool {}
 }