[Tunnelbroker] match JS naming convention

Summary:
This was requested few times in the previous diffs.

Depends on: D8957

Test Plan:

• run test
• check if keyserver can connect to Tunnelbroker

Reviewers: bartek, michal, varun, jon

Reviewed By: bartek, michal

Subscribers: ashoat, tomek

Differential Revision: https://phab.comm.dev/D9128