Auto-select available port for localhost (#179)

[piri-p]

Fix #179 - Auto-select available port for localhost @whimboo
Not sure how to write test cases for this. From local debugging, it indeed auto-selects available port

[whimboo]

While this is testing code I don't think that we need a specific test case for that change. I've tried locally as well and it works like a charm as you already mentioned.

Thank you for the fix!