Improve HTTP timeout message

[michaelwood]

We send back a generic server error (500) when we get a file with a timeout issue. Capture this and send back the HTTP error message.

TimeoutError: [Errno 110] Connection timed out
  File "urllib3/connection.py", line 198, in _new_conn
    sock = connection.create_connection(
  File "urllib3/util/connection.py", line 85, in create_connection
    raise err
  File "urllib3/util/connection.py", line 73, in create_connection
    sock.connect(sa)
ConnectTimeoutError: (<urllib3.connection.HTTPSConnection object at 0x7d9350a229f0>, 'Connection to lrfoundation.org.uk timed out. (connect timeout=None)')
  File "urllib3/connectionpool.py", line 787, in urlopen
    response = self._make_request(
  File "urllib3/connectionpool.py", line 488, in _make_request
    raise new_e
  File "urllib3/connectionpool.py", line 464, in _make_request
    self._validate_conn(conn)
  File "urllib3/connectionpool.py", line 1093, in _validate_conn
    conn.connect()
  File "urllib3/connection.py", line 704, in connect
    self.sock = sock = self._new_conn()
  File "urllib3/connection.py", line 207, in _new_conn
    raise ConnectTimeoutError(
MaxRetryError: HTTPSConnectionPool(host='lrfoundation.org.uk', port=443): Max retries exceeded with url: /sites/default/files/2025-04/lrf_360giving_master_sheet_as_of_16.10.24-2.xlsx (Caused by ConnectTimeoutError(<urllib3.connection.HTTPSConnection object at 0x7d9350a229f0>, 'Connection to lrfoundation.org.uk timed out. (connect timeout=None)'))
  File "requests/adapters.py", line 667, in send
    resp = conn.urlopen(
  File "urllib3/connectionpool.py", line 841, in urlopen
    retries = retries.increment(
  File "urllib3/util/retry.py", line 519, in increment
    raise MaxRetryError(_pool, url, reason) from reason  # type: ignore[arg-type]
ConnectTimeout: HTTPSConnectionPool(host='lrfoundation.org.uk', port=443): Max retries exceeded with url: /sites/default/files/2025-04/lrf_360giving_master_sheet_as_of_16.10.24-2.xlsx (Caused by ConnectTimeoutError(<urllib3.connection.HTTPSConnection object at 0x7d9350a229f0>, 'Connection to lrfoundation.org.uk timed out. (connect timeout=None)'))
  File "cove/input/views.py", line 78, in data_input
    data.download()
  File "cove/input/models.py", line 72, in download
    r = requests.get(
  File "requests/api.py", line 73, in get
    return request("get", url, params=params, **kwargs)
  File "requests/api.py", line 59, in request
    return session.request(method=method, url=url, **kwargs)
  File "requests/sessions.py", line 589, in request
    resp = self.send(prep, **send_kwargs)
  File "requests/sessions.py", line 703, in send
    r = adapter.send(request, **kwargs)
  File "requests/adapters.py", line 688, in send
    raise ConnectTimeout(e, request=request)
TypeError: format requires a mapping
  File "django/core/handlers/exception.py", line 55, in inner
    response = get_response(request)
  File "django/core/handlers/base.py", line 197, in _get_response
    response = wrapped_callback(request, *callback_args, **callback_kwargs)
  File "django/utils/decorators.py", line 134, in _wrapper_view
    response = view_func(request, *args, **kwargs)
  File "cove/input/views.py", line 88, in data_input
    'sub_title': _(
  File "django/utils/functional.py", line 191, in __mod__
    return str(self) % rhs