[3.13] pythongh-131263: Skip test_timerfd_negative on NetBSD to prevent system freeze (pythonGH-131431) (python#131451)

pythongh-131263: Skip test_timerfd_negative on NetBSD to prevent system freeze (pythonGH-131431)
(cherry picked from commit 8ad4646)

Co-authored-by: Furkan Onder <furkanonder@protonmail.com>

Author: miss-islington

Lib/test/test_os.py

@@ -4188,6 +4188,9 @@ def test_timerfd_non_blocking(self):
         # confirm if timerfd is readable and read() returns 1 as bytes.
         self.assertEqual(self.read_count_signaled(fd), 1)
 
+    @unittest.skipIf(sys.platform.startswith('netbsd'),
+                     "gh-131263: Skip on NetBSD due to system freeze "
+                     "with negative timer values")
     def test_timerfd_negative(self):
         one_sec_in_nsec = 10**9
         fd = self.timerfd_create(time.CLOCK_REALTIME)