Fix #10098. Fix sporadic test_os failures.

Amaury noticed that we're not waiting for the subprocess to be ready --
it should be checking for 1, not 0.

Lib/test/test_os.py

@@ -1042,7 +1042,7 @@ class Win32KillTests(unittest.TestCase):
         # Let the interpreter startup before we send signals. See #3137.
         count, max = 0, 20
         while count < max and proc.poll() is None:
-            if m[0] == 0:
+            if m[0] == 1:
                 break
             time.sleep(0.5)
             count += 1