Fixed frontend still showing an empty instrument catalog after user session is expired

With this change the frontend will perform a user logout when any request responds with 401 which means that the user is no longer authorized (session expired after being logged in). That way, as soon as the user tries to do anything after session was expired, MPIC will redirect to the only-login landing page

Also taking the opportunity to tweak a bit the "gohome" link. Now logo + title are the same link and the cursor transforms to "pointer" to be more intuitive

Closes T369228