Updating test case logic to check if netsvc_module exists (#3418)

* updating netsvc_module path check to use sudo

* formatting the file as per flake8 recommendations

* removing string formatting for ls.path_exists()

microsoft/testsuites/network/networksettings.py

@@ -3,7 +3,6 @@
 
 import re
 import time
-from pathlib import PurePosixPath
 from typing import Any, Dict, List, Tuple, Union, cast
 
 from assertpy import assert_that
@@ -24,7 +23,7 @@
 )
 from lisa.base_tools import Uname
 from lisa.operating_system import BSD, Debian, Redhat, Suse, Ubuntu, Windows
-from lisa.tools import Ethtool, Iperf3, KernelConfig, Modinfo, Nm
+from lisa.tools import Ethtool, Iperf3, KernelConfig, Ls, Modinfo, Nm
 from lisa.util import parse_version
 from microsoft.testsuites.network.common import cleanup_iperf3
 
@@ -731,10 +730,10 @@ def _check_msg_level_change_supported(self, node: Node) -> None:
                     cwd=node.working_path,
                 ).stdout
 
-            assert node.shell.exists(
-                PurePosixPath(netvsc_module)
+            ls = node.tools[Ls]
+            assert ls.path_exists(
+                netvsc_module, sudo=True
             ), f"{netvsc_module} doesn't exist."
-
             nm = node.tools[Nm]
             msg_level_symbols = nm.get_symbol_table(netvsc_module)
         else: