adding output file location option

[paigerube14]

need to be able to set where the output file is written to based on certain permissions

https://gcsweb-ci.apps.ci.l2s4.p1.openshiftapps.com/gcs/origin-ci-test/pr-logs/pull/openshift_release/39697/rehearse-39697-periodic-ci-redhat-chaos-krkn-hub-main-krkn-hub-tests/1671888375042281472/artifacts/krkn-hub-tests/redhat-chaos-cerberus/build-log.txt

+ python3 /root/cerberus/start_cerberus.py --config=/tmp/tmp.YzZXKPpakF/cerberus_config.yaml
Traceback (most recent call last):
  File "/root/cerberus/start_cerberus.py", line 557, in <module>
    handlers=[logging.FileHandler("cerberus.report", mode="w"), logging.StreamHandler()],
  File "/usr/lib64/python3.9/logging/__init__.py", line 1146, in __init__
    StreamHandler.__init__(self, self._open())
  File "/usr/lib64/python3.9/logging/__init__.py", line 1175, in _open
    return open(self.baseFilename, self.mode, encoding=self.encoding,
PermissionError: [Errno 13] Permission denied: '/cerberus/cerberus.report'