Run curl_setopt_ssl.phpt on Windows

There seems to be no particular reason to skip this test on Windows.

While we're at it, we also remove the check for `proc_open()` since
this function is required (and checked) by run-tests.php anyway.

Author: cmb69

ext/curl/tests/curl_setopt_ssl.phpt

@@ -4,10 +4,8 @@ CURLOPT_SSL* basic client auth tests
 curl
 --SKIPIF--
 <?php
-if (!function_exists("proc_open")) die("skip no proc_open");
 exec('openssl version', $out, $code);
 if ($code > 0) die("skip couldn't locate openssl binary");
-if (PHP_OS_FAMILY === 'Windows') die('skip not for Windows');
 if (PHP_OS_FAMILY === 'Darwin') die('skip Fails intermittently on macOS');
 if (PHP_OS === 'FreeBSD') die('skip proc_open seems to be stuck on FreeBSD');
 $curl_version = curl_version();