download_get error in tests

[sckott]

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ERROR: occurrences.download_get - basic test
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Traceback (most recent call last):
  File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/nose/case.py", line 198, in runTest
    self.test(*self.arg)
  File "/Users/sckott/github/sac/pygbif/test/test-occurrences-download_get.py", line 8, in test_download_get
    res = occ.download_get(key)
  File "/Users/sckott/github/sac/pygbif/pygbif/occurrences/download.py", line 400, in download_get
    gbif_GET_write(url, path, **kwargs)
  File "/Users/sckott/github/sac/pygbif/pygbif/gbifutils.py", line 56, in gbif_GET_write
    raise NoResultException("content-type did not contain '%s'" % ctype)
pygbif.gbifutils.NoResultException: content-type did not contain 'application/octet-stream'