Fix default location of logrotate config file. This is exapmle error output:
root@turris-test:~# sentinel-nikola
error: cannot stat /etc/logrotate.d/iptables: No such file or directory
Exception thrown: Command '('/usr/sbin/logrotate', '-f', '/etc/logrotate.d/iptables')' returned non-zero exit status 1.
Exception traceback: [<FrameSummary file /usr/lib/python3.7/site-packages/sentinel_nikola/__main__.py, line 65 in main>, <FrameSummary file /usr/lib/python3.7/site-packages/sentinel_nikola/__main__.py, line 94 in rotate_syslog_file>, <FrameSummary file /usr/lib/python3.7/subprocess.py, line 411 in check_output>, <FrameSummary file /usr/lib/python3.7/subprocess.py, line 512 in run>]