snapcraft login should check namespace status

[Rex Tsai]

snapcraft login stops to check the namespace status but return a useless error message - "Unexpected error when obtaining your account information.".

The user needs to login dashboard.snapcraft.io and set the namespace to solve the login issue.

eg,
snapcraft login
Enter your Ubuntu One SSO credentials.
Email: <email address hidden>
Password:

We strongly recommend enabling multi-factor authentication: https://help.ubuntu.com/community/SSO/FAQs/2FA
Do you agree to the developer terms and conditions. (https://dashboard.snapcraft.io/dev/agreements/new/)? [y/N] y
Unexpected error when obtaining your account information.
Login failed.

Ref
* Unexpected error when obtaining your account information. Login failed - snapcraft - snapcraft.io - https://forum.snapcraft.io/t/unexpected-error-when-obtaining-your-account-information-login-failed/1960

[Daniel Manrique (roadmr)]

Marking this bug as confirmed because I just ran into it in the context of helping a user with no namespace set.

Note that the store is returning a 403 response with an error_list containing the appropriate message indicating exactly what the problem is. Just bubbling this up to the user should take care of things.