Improve cleanup lifecycle readability

Signed-off-by: Loren Eteval <loren.eteval@proton.me>

tests/test_sing_tun_linux_host.py

@@ -161,8 +161,10 @@ class SingTUNLinuxHostTest(unittest.TestCase):
         def wait(timeout=None):
             self.assertIsNone(timeout)
             entered.set()
+
             if not authorized.wait(5):
                 raise RuntimeError('fixture authorization was not released')
+
             process.poll.return_value = 0
             return 0
 
@@ -173,6 +175,7 @@ class SingTUNLinuxHostTest(unittest.TestCase):
                 self.host.execute([['ip', 'link', 'delete', 'dev', 'utun101']])
             except Exception as ex:
                 # Any non-exit exceptions
+
                 errors.append(ex)
             finally:
                 complete.set()
@@ -182,6 +185,7 @@ class SingTUNLinuxHostTest(unittest.TestCase):
         ), mock.patch.object(self.module.subprocess, 'Popen', return_value=process):
             worker = threading.Thread(target=recover)
             worker.start()
+
             try:
                 self.assertTrue(entered.wait(2))
                 self.assertFalse(complete.is_set())
@@ -269,8 +273,10 @@ class SingTUNLinuxHostTest(unittest.TestCase):
 
         self.assertIs(self.host._process, process)
         self.assertTrue(directory.exists())
+
         process.poll.return_value = 126
         self.host.drain()
+
         self.assertFalse(directory.exists())
 
     def testLiveForwarderDnsCannotBeReportedAsRestored(self):