Requesting too much data results in gateway timeout

[sentry-io[bot]]

We should place a limit on the amount of data that can be retrieved with a single request Sentry Issue: DASHBOARD-1X

HTTPError: 504 Server Error: Gateway Time-out for url: https://api.solarforecastarbiter.org/observations/063d42da-99fe-11e9-8674-0a580a8200c9/values?start=2017-05-01T17%3A04%3A00%2B00%3A00&end=2020-05-04T17%3A04%3A00%2B00%3A00
(9 additional frame(s) were not displayed)
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  File "sfa_dash/blueprints/base.py", line 25, in insert_plot
    uuid, params={'start': start, 'end': end})
  File "sfa_dash/api_interface/observations.py", line 10, in get_values
    req = get_request(f'/observations/{observation_id}/values', **kwargs)
  File "sfa_dash/api_interface/__init__.py", line 26, in get_request
    f'{app.config["SFA_API_URL"]}{path}', **kwargs))
  File "sfa_dash/api_interface/util.py", line 62, in handle_response
    request_object.raise_for_status()
  File "requests/models.py", line 940, in raise_for_status
    raise HTTPError(http_error_msg, response=self)

[sentry-io[bot]]

Sentry issue: DASHBOARD-1Y