[services] Tunnelbroker - Change RabbitMQ queue name for a sandbox mode

Summary:
When running in a sandbox mode Tunnelbroker uses a different config file which is tunnelbroker-dev.ini. In a sandbox mode, we are using a test prefix for database table names.
To follow this approach we should use a test name for a RabbitMQ queue instead of the default one.

Related Linear task: ENG-1491

Test Plan: Successfully passing unit tests from D4749.

Reviewers: karol, tomek

Reviewed By: karol, tomek

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

Differential Revision: https://phab.comm.dev/D4753