Fix test configuration for auth tests

[IanMayo]

Summary

• Enable auth mode in test configuration with required env vars (AUTH, TOKEN_SECRET, initial user credentials)
• Add --forceExit to Jest for clean test exit
• Add .unref() to token cleanup interval to prevent blocking process exit
• Bump version to 0.8.3 (also syncs swagger.json which was at 0.8.1)

Test plan

• All 35 unit tests pass
• No worker process exit warnings

[thevahidal]

Hi @IanMayo, Thanks for the PR.
I reviewed these changes in the previous PR, should we merge them separately or just merge the previous one and close this?

[IanMayo]

Hello @thevahidal - I saw this as a separate issue, so it seemed tidier to fix this on main first, then the second one just relates to the sqlite dependency.

[thevahidal]

I agree @IanMayo, then please apply the comments I asked on the other one, onto this one.