No stack traces for read timeouts

[lkiesow]

Similar to #34, we don't need full stack traces for read timeouts.

We want something like

 ERROR:occameracontrol.metrics:Failed to communicate with camera 'arec-15-421' @ 'http://camera1-15-421.example.com': requests.exceptions.ReadTimeout: HTTPConnectionPool(host='camera1-15-421.example.com', port=80): Read timed out. (read timeout=5)

Instead of getting

 ERROR:occameracontrol.metrics:Failed to communicate with camera 'arec-15-421' @ 'http://camera1-15-421.example.com'
 Traceback (most recent call last):
   File "/usr/lib/python3.9/site-packages/urllib3/connectionpool.py", line 446, in _make_request
     six.raise_from(e, None)
   File "<string>", line 3, in raise_from
   File "/usr/lib/python3.9/site-packages/urllib3/connectionpool.py", line 441, in _make_request
     httplib_response = conn.getresponse()
   File "/usr/lib64/python3.9/http/client.py", line 1377, in getresponse
     response.begin()
   File "/usr/lib64/python3.9/http/client.py", line 320, in begin
     version, status, reason = self._read_status()
   File "/usr/lib64/python3.9/http/client.py", line 281, in _read_status
     line = str(self.fp.readline(_MAXLINE + 1), "iso-8859-1")
   File "/usr/lib64/python3.9/socket.py", line 704, in readinto
     return self._sock.recv_into(b)
 socket.timeout: timed out
 During handling of the above exception, another exception occurred:
 Traceback (most recent call last):
   File "/usr/lib/python3.9/site-packages/requests/adapters.py", line 439, in send
     resp = conn.urlopen(
   File "/usr/lib/python3.9/site-packages/urllib3/connectionpool.py", line 756, in urlopen
     retries = retries.increment(
   File "/usr/lib/python3.9/site-packages/urllib3/util/retry.py", line 532, in increment
     raise six.reraise(type(error), error, _stacktrace)
   File "/usr/lib/python3.9/site-packages/urllib3/packages/six.py", line 709, in reraise
     raise value
   File "/usr/lib/python3.9/site-packages/urllib3/connectionpool.py", line 700, in urlopen
     httplib_response = self._make_request(
   File "/usr/lib/python3.9/site-packages/urllib3/connectionpool.py", line 448, in _make_request
     self._raise_timeout(err=e, url=url, timeout_value=read_timeout)
   File "/usr/lib/python3.9/site-packages/urllib3/connectionpool.py", line 337, in _raise_timeout
     raise ReadTimeoutError(
 urllib3.exceptions.ReadTimeoutError: HTTPConnectionPool(host='camera1-15-421.example.com', port=80): Read timed out. (read timeout=5)
 During handling of the above exception, another exception occurred:
 Traceback (most recent call last):
   File "/usr/lib/python3.9/site-packages/occameracontrol/__main__.py", line 60, in control_camera
     camera.update_position()
   File "/usr/lib/python3.9/site-packages/occameracontrol/camera.py", line 147, in update_position
     self.move_to_preset(self.preset_inactive)
   File "/usr/lib/python3.9/site-packages/occameracontrol/camera.py", line 86, in move_to_preset
     response = requests.get(url, auth=auth, params=params, timeout=5)
   File "/usr/lib/python3.9/site-packages/requests/api.py", line 76, in get
     return request('get', url, params=params, **kwargs)
   File "/usr/lib/python3.9/site-packages/requests/api.py", line 61, in request
     return session.request(method=method, url=url, **kwargs)
   File "/usr/lib/python3.9/site-packages/requests/sessions.py", line 544, in request
     resp = self.send(prep, **send_kwargs)
   File "/usr/lib/python3.9/site-packages/requests/sessions.py", line 657, in send
     r = adapter.send(request, **kwargs)
   File "/usr/lib/python3.9/site-packages/requests/adapters.py", line 529, in send
     raise ReadTimeout(e, request=request)
 requests.exceptions.ReadTimeout: HTTPConnectionPool(host='camera1-15-421.example.com', port=80): Read timed out. (read timeout=5)