Testing: allow users to pass TEST-TIMEOUT-MS as param for complete-topology

It would be nice if `complete-topology` allowed a user to pass in the default timeout as a parameter (rather than just setting it as `5000ms`). I had a test that kept failing by taking too long. 

This PR adds functionality without breaking any existing code. Tests pass.

(PS - not sure if this is the proper way to submit a PR for an apache project. I'm open to feedback. Thanks)