Tests: unit_stop() removed where possible.

Since wait_for_record() was introduced there is no need
to stop Unit before parsing unit.log.

test/test_usr1.py

@@ -1,7 +1,6 @@
 import os
 from subprocess import call
 
-from conftest import unit_stop
 from unit.applications.lang.python import TestApplicationPython
 from unit.utils import waitforfiles
 
@@ -41,8 +40,6 @@ class TestUSR1(TestApplicationPython):
 
         assert self.get(url='/usr1')['status'] == 200
 
-        unit_stop()
-
         assert (
             self.wait_for_record(r'"GET /usr1 HTTP/1.1" 200 0 "-" "-"', log)
             is not None
@@ -74,8 +71,6 @@ class TestUSR1(TestApplicationPython):
         body = 'body_for_a_log_unit'
         assert self.post(body=body)['status'] == 200
 
-        unit_stop()
-
         assert self.wait_for_record(body) is not None, 'rename new'
         assert self.search_in_log(body, log_new) is None, 'rename new 2'