Fix: Fix NTP config long jump test failure issue (#13671)

The restart command needs to be run using root privilege.

Author: wumiaont

tests/common/plugins/conditional_mark/tests_mark_conditions.yaml

@@ -889,13 +889,6 @@ ntp/test_ntp.py::test_ntp:
     conditions:
       - https://github.com/sonic-net/sonic-buildimage/issues/19425
 
-ntp/test_ntp.py::test_ntp_long_jump_disabled:
-  # Due to NTP code bug, long jump will still happen after disable it.
-  # Set xfail flag for this test case
-  xfail:
-    strict: True
-    reason: "Known NTP bug"
-
 #######################################
 #####           pc               #####
 #######################################

tests/ntp/test_ntp.py

@@ -39,9 +39,9 @@ def config_long_jump(duthost, enable=False):
             regex = "s/NTPD_OPTS='-g'/NTPD_OPTS='-x'/"
 
     if using_ntpsec:
-        duthost.command("sed -i '%s' /etc/default/ntpsec" % regex)
+        duthost.command("sudo sed -i '%s' /etc/default/ntpsec" % regex)
     else:
-        duthost.command("sed -i %s /etc/default/ntp" % regex)
+        duthost.command("sudo sed -i %s /etc/default/ntp" % regex)
     duthost.service(name='ntp', state='restarted')
 
 
@@ -148,8 +148,8 @@ def test_ntp_long_jump_disabled(duthosts, rand_one_dut_hostname, setup_ntp, setu
 
     config_long_jump(duthost, enable=False)
 
-    if wait_until(720, 10, 0, check_ntp_status, duthost):
-        pytest.fail("NTP long jump disable failed")
+    pytest_assert(wait_until(720, 10, 0, check_ntp_status, duthost),
+                  "NTP long jump disable failed")
 
 
 def run_ntp(duthosts, rand_one_dut_hostname, setup_ntp):