Fix authentication for bots

[AminArria]

#665 left an open issue for authentication and bots, currently we still support unauthenticated joining a match because bots don't have an authentication mechanism

To solve this we should have a way to generate a bot JWT that we can use for bots to connect, this JWT doesn't have to be unique per game nor per bot. We can have a sort of global JWT used by all bots and that we cache in the bot_manager app. Bonus point, if we reuse a device_id then we simply use the existing /auth/refresh-token endpoint for refreshing this token