bpo-41439: Skip test_ssl and test_uuid tests if fork() is not supported (GH-21684)

diff --git a/Lib/test/test_ssl.py b/Lib/test/test_ssl.py
index e5cd962..67850c3 100644
--- a/Lib/test/test_ssl.py
+++ b/Lib/test/test_ssl.py
@@ -391,7 +391,7 @@ def test_random(self):
         ssl.RAND_add(b"this is a random bytes object", 75.0)
         ssl.RAND_add(bytearray(b"this is a random bytearray object"), 75.0)
 
-    @unittest.skipUnless(os.name == 'posix', 'requires posix')
+    @unittest.skipUnless(hasattr(os, 'fork'), 'need os.fork')
     def test_random_fork(self):
         status = ssl.RAND_status()
         if not status: