The clue indicates that we should somehow manipulate the cookie in order to get
logged-in as admin.

So I first browsed around the site to see what cookies get set, but all we get
is the same encrypted cookie we can see on other problems. Looks like we have
to forge a new cookie.

It was then a matter of guesswork :

- `username=admin` : Nope.
- `user=admin` : Nope.
- `admin=True` (similar as the previous "Logon" task) : we get the flag: `picoCTF{n0l0g0n_n0_pr0bl3m_26b0181a}`