Handle session expiry/authentication failures

[eviljeff]

If auth has expired for code manager the app just shows the 401 returned by the API as an error, but doesn't log out the user in the local state or suggest how to rectify (i.e. login again). Refreshing the page fixes it.

┆Issue is synchronized with this Jira Task

[eviljeff]

see mozilla/addons#8690 for a screenshot and some background