Inconsistent logout behaviour reset timezone and locale

[samuelwei]

Describe the bug

• Timezone is currently reset on a regular logout, locale is not reset
• On a logout caused by an unauth. error, neither the locale nor the timezone is reset

Expected behavior A consistent behaviour for all logout events See #1521 for how to communicate timezone to user

Additional context During login the locale and timezone saved in the user profile are always applied

ToDo

• [ ] Add to cypress tests