[python-pytrakt] Feature: Add Bad Gateway exception

[glensc]

This ensures 502 responses don't get json decode exceptions

  File "/python-3.10.1/lib/python3.10/site-packages/trakt/core.py", line 533, in _handle_request
    json_data = json.loads(response.content.decode('UTF-8', 'ignore'))
  File "/usr/local/Cellar/python@3.10/3.10.1/Frameworks/Python.framework/Versions/3.10/lib/python3.10/json/__init__.py", line 346, in loads
    return _default_decoder.decode(s)
  File "/usr/local/Cellar/python@3.10/3.10.1/Frameworks/Python.framework/Versions/3.10/lib/python3.10/json/decoder.py", line 337, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "/usr/local/Cellar/python@3.10/3.10.1/Frameworks/Python.framework/Versions/3.10/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)

[glensc]

Carried to my fork:

• glensc/python-pytrakt@edb257e