parse_cookie_str can be crashed by end users via cookie_str = 'true'

[gmseb]

Hi!

I stumbled upon a crash report ValueError: not enough values to unpack (expected 2, got 1) in Sentry from django-cookie-consent code line…

django-cookie-consent/cookie_consent/util.py

Line 15 in 81aae63

key, value = c.split("=")

…today. cookie_str has value "true" in this case, and playing with IPython shows how the current code breaks:

In [1]: 'foo=bar'.split('=')
Out[1]: ['foo', 'bar']

In [2]: ''.split('=')
Out[2]: ['']

In [3]: 'true'.split('=')
Out[3]: ['true']

The issue still exists on master so until this is fixed, Django setups can be crashed like this. Would be great to have fixed, thank you!

Best, Sebastian