shub: 500 Server Error when trying to deploy

Hello,

Usually I deploy with `shub image upload` but since today, after my custom image has been pushed to SH, I get this error (either with 2.6.1 or 2.8.0):

Traceback (most recent call last):
  File "/home/itdataimpact/projets/crawling_v2/.direnv/python-2.7.15/bin/shub", line 11, in <module>
    sys.exit(cli())
  File "/home/itdataimpact/projets/crawling_v2/.direnv/python-2.7.15/lib/python2.7/site-packages/click/core.py", line 722, in __call__
    return self.main(*args, **kwargs)
  File "/home/itdataimpact/projets/crawling_v2/.direnv/python-2.7.15/lib/python2.7/site-packages/click/core.py", line 697, in main
    rv = self.invoke(ctx)
  File "/home/itdataimpact/projets/crawling_v2/.direnv/python-2.7.15/lib/python2.7/site-packages/click/core.py", line 1066, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/home/itdataimpact/projets/crawling_v2/.direnv/python-2.7.15/lib/python2.7/site-packages/click/core.py", line 1066, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/home/itdataimpact/projets/crawling_v2/.direnv/python-2.7.15/lib/python2.7/site-packages/click/core.py", line 895, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/home/itdataimpact/projets/crawling_v2/.direnv/python-2.7.15/lib/python2.7/site-packages/click/core.py", line 535, in invoke
    return callback(*args, **kwargs)
  File "/home/itdataimpact/projets/crawling_v2/.direnv/python-2.7.15/lib/python2.7/site-packages/shub/image/upload.py", line 40, in cli
    async, skip_tests)
  File "/home/itdataimpact/projets/crawling_v2/.direnv/python-2.7.15/lib/python2.7/site-packages/shub/image/upload.py", line 50, in upload_cmd
    apikey, insecure, async)
  File "/home/itdataimpact/projets/crawling_v2/.direnv/python-2.7.15/lib/python2.7/site-packages/shub/image/deploy.py", line 95, in deploy_cmd
    req.raise_for_status()
  File "/home/itdataimpact/projets/crawling_v2/.direnv/python-2.7.15/lib/python2.7/site-packages/requests/models.py", line 939, in raise_for_status
    raise HTTPError(http_error_msg, response=self)
requests.exceptions.HTTPError: 500 Server Error: Internal Server Error for url: https://app.scrapinghub.com/api/releases/deploy.json