Bug: CIIP: user doesn't see the "your session expired" message on the login page, when their session expired

[pbastia]

Describe the Bug:

When the session expires, the user is redirected to the "You must be logged in" page instead of seeing the "your session expired" message

Probability (1-5): 2
Effect (1-5):1

Steps to reproduce the behaviour:
Login, wait 30 min for session to expire, then navigate somewhere else on the app

Dev checklist

• the <SessionTimeoutHandler> component needs to be inline, above the <PageRedirectHandler in _app.tsx
• the <SessionTimeoutHandler> needs to have had at least one request successful to the session remaining time endpoint, in order to add the URL parameter when redirecting.