template fix for only_normal_samples_event

[buehlere]

cc still present in template for an only_normal_samples_event, causing the following error:

raised unexpected: KeyError('cc')
Traceback (most recent call last):
  File "/srv/services/beagle/code/beagle/notifier/event_handler/event_handler.py", line 19, in process
    self.logger.debug("[%s]: %s", e.get_type(), str(e))
  File "/srv/services/beagle/code/beagle/notifier/events/only_normal_samples_event.py", line 22, in __str__
    return TEMPLATE.format(request_id=self.request_id)
KeyError: 'cc'