[copy_duplicate_info] KeyError: 'bug_count'

[sentry]

Sentry Issue: BUGBOT-17

KeyError: 'bug_count'
(3 additional frame(s) were not displayed)
...
  File "bugbot/bzcleaner.py", line 858, in run
    self.send_email(date=date)
  File "bugbot/bzcleaner.py", line 771, in send_email
    data = self.get_email_data(date)
  File "bugbot/bzcleaner.py", line 689, in get_email_data
    bugs = self.get_bugs(date=date)
  File "copy_duplicate_info.py", line 99, in get_bugs
    bugs = super(CopyDuplicateInfo, self).get_bugs(date=date, bug_ids=bug_ids)
  File "bugbot/bzcleaner.py", line 464, in get_bugs
    ).get_data().wait()

Rule copy_duplicate_info