"round" may bump 1 second to 2 if sleep takes more than 1.49 sec

Use less than 2 as a way to account for test on slower systems.
This is a follow up to: https://review.opendev.org/#/c/691883/

Trivial-Fix

Change-Id: Ia313b9c4028f0242cb0da8764b9921c5c30c465a
Fixes-Bug: #1891517

neutron/tests/unit/common/test_utils.py

@@ -542,13 +542,13 @@ class TimerTestCase(base.BaseTestCase):
     def test__getattr(self):
         with utils.Timer() as timer:
             time.sleep(1)
-        self.assertEqual(1, round(timer.total_seconds()))
+        self.assertLess(timer.total_seconds(), 2)
         self.assertEqual(1, timer.delta.seconds)
 
     def test__enter_with_timeout(self):
         with utils.Timer(timeout=10) as timer:
             time.sleep(1)
-        self.assertEqual(1, round(timer.total_seconds()))
+        self.assertLess(timer.total_seconds(), 2)
 
     def test__enter_with_timeout_exception(self):
         msg = r'Timer timeout expired after 1 second\(s\).'