[services] Tunnelbroker - Fix scripts in Dockerfiles

Summary:
Raised in https://phabricator.ashoat.com/D3988#112748

I mistakenly put run_service.sh instead of run_tests.sh

Test Plan:

cd services
yarn test-tunnelbroker-service

This should run tunnelbroker tests

Reviewers: max, ashoat, tomek

Reviewed By: max, ashoat

Subscribers: jon, ashoat, tomek, adrian, atul, abosh

Differential Revision: https://phab.comm.dev/D4052