[Feat]: code-server kill all sessions

## What is your suggestion?
implement a feature to kill all sessions such that one needs to sign in to code server by explicitly entering the authentication password.

## Why do you want this feature?
Our team uses code-server and when our team member leaves, we cannot remove access for him as he is already signed in from his browser and we can never log him out as even password change doesn't effect the existing session

## Are there any workarounds to get this functionality today?
no

## Are you interested in submitting a PR for this?

no