logrotate.py: fix testimage occasionally failure

testcase test_systemd_failed occasionally failed with below error:
Failed to start Rotate log files.
logrotate.service: Failed with result 'exit-code'.
logrotate.service: Main process exited, code=exited, status=1/FAILURE
error: stat of /var/log/logrotate_test failed: No such file or directory
error: logrotate_test:1 lines must begin with a keyword or a filename (possibly in double quotes)

above failure caused since testcase test_logrotate_wtmp
add /etc/logrotate.d/logrotate_test, which need /var/log/logrotate_test,
but there is no such file. so when logrotate.service is triggerd
by logrotate.timer after testcase test_logrotate_wtmp is runned,
the testcase test_systemd_failed will fail.

these 3 lines are useless, so remove them to fix above problem.

(From OE-Core rev: 22f5f7f86a4d47624c476be00e5121009c48cb7b)

Signed-off-by: Changqing Li <changqing.li@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/lib/oeqa/runtime/cases/logrotate.py

@@ -37,10 +37,6 @@ class LogrotateTest(OERuntimeTestCase):
         msg = ('Could not write to /tmp/logrotate-test.conf')
         self.assertEqual(status, 0, msg = msg)
         
-        status, output = self.target.run('echo "/var/log/logrotate_test {\\n missingok \\n monthly \\n rotate 1" > /etc/logrotate.d/logrotate_test')
-        msg = ('Could not write to /etc/logrotate.d/logrotate_test')
-        self.assertEqual(status, 0, msg = msg)
-        
         # If logrotate fails to rotate the log, view the verbose output of logrotate to see what prevented it
         _, logrotate_output = self.target.run('logrotate -vf /tmp/logrotate-test.conf')
         status, _ = self.target.run('find $HOME/logrotate_dir -type f | grep wtmp.1')