Crashin with ValueError when passing a HTTP_Authorization header that doesn't have space in it.

[driesdesmet]

Because of this line in the middleware:

method, claim = request.META['HTTP_AUTHORIZATION'].split(' ', 1)

any request created with such a header without a space is getting:

ValueError: need more than 1 value to unpack

I've manually replaced this with:

try:
    method, claim = request.META['HTTP_AUTHORIZATION'].split(' ', 1)
except ValueError:
    logger.debug('HTTP_AUTHORIZATION does not have the right format for asymmetric JWT authentication.')
    return

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