If the camera gives a CommError (for example because it's not reachable)
when calling _generate_token, the _token should be unset, as otherwise
the token will be reused for every command and it won't be (re)generated
correctly when the camera is back online.
Coverage decreased (-0.1%) to 31.818% when pulling e75b64b67fe167b7bbfdb1b1b355b1b317d30752 on antlarr:master into 625f8577300693a2b46c3acf39694e46d72073d9 on tchellomello:master.
If the camera gives a CommError (for example because it's not reachable) when calling _generate_token, the _token should be unset, as otherwise the token will be reused for every command and it won't be (re)generated correctly when the camera is back online.