Update Lib/test/test_statistics.py

Co-authored-by: Gregory P. Smith <68491+gpshead@users.noreply.github.com>

Author: rhettinger

Lib/test/test_statistics.py

@@ -2116,6 +2116,8 @@ def test_gh_140938(self):
         # Inputs with math.inf should raise a ValueError
         with self.assertRaises(ValueError):
             self.func([1.0, math.inf])
+        with self.assertRaises(ValueError):
+            self.func([1.0, math.nan])
 
 
 class TestSqrtHelpers(unittest.TestCase):