Crash in crashmanager.cron.bug_update_status

Found in logs on server while testing:

Traceback (most recent call last):
  File "/home/worker/.local/lib/python3.10/site-packages/requests/models.py", line 974, in json
    return complexjson.loads(self.text, **kwargs)
  File "/usr/local/lib/python3.10/json/__init__.py", line 346, in loads
    return _default_decoder.decode(s)
  File "/usr/local/lib/python3.10/json/decoder.py", line 337, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "/usr/local/lib/python3.10/json/decoder.py", line 355, in raw_decode
    raise JSONDecodeError("Expecting value", s, err.value) from None
json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0)

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/worker/.local/lib/python3.10/site-packages/celery/app/trace.py", line 477, in trace_task
    R = retval = fun(*args, **kwargs)
  File "/home/worker/.local/lib/python3.10/site-packages/celery/app/trace.py", line 760, in __protected_call__
    return self.run(*args, **kwargs)
  File "/src/server/crashmanager/cron.py", line 69, in bug_update_status
    call_command("bug_update_status")
  File "/home/worker/.local/lib/python3.10/site-packages/django/core/management/__init__.py", line 194, in call_command
    return command.execute(*args, **defaults)
  File "/home/worker/.local/lib/python3.10/site-packages/django/core/management/base.py", line 458, in execute
    output = self.handle(*args, **options)
  File "/src/server/crashmanager/management/commands/bug_update_status.py", line 33, in handle
    bugStatus = providerInstance.getBugStatus(bugIds, username, password)
  File "/src/server/crashmanager/Bugtracker/BugzillaProvider.py", line 61, in getBugStatus
    bugs = bz.getBugStatus(bugIds)
  File "/src/server/crashmanager/Bugtracker/BugzillaREST.py", line 77, in getBugStatus
    return self.getBugs(
  File "/src/server/crashmanager/Bugtracker/BugzillaREST.py", line 110, in getBugs
    json = response.json()
  File "/home/worker/.local/lib/python3.10/site-packages/requests/models.py", line 978, in json
    raise RequestsJSONDecodeError(e.msg, e.doc, e.pos)
requests.exceptions.JSONDecodeError: Expecting value: line 1 column 1 (char 0)

Start with crashmanager/cron.py:69 and crashmanager/management/commands/bug_update_status.py:33, then trace BugzillaProvider.py:61 into BugzillaREST.py:77 and :110. Reproduce the bug_update_status path and determine the expected behavior when the Bugzilla response is not JSON; done means that behavior is verified without the cron task crashing.