Support dual binding for http and https for test-proxy wrapper

See #4345 for more context, but basically we should be able to bind both `http://0.0.0.0:0` and `https://0.0.0.0:0` and listen for both. See .NET's implementation for an example. I don't think we have any need for http binding right now, so putting this on the backlog.

Start with issue #4345 for the test-proxy wrapper context, then compare the requested behavior with .NET's implementation. Trace how the wrapper currently handles bindings and verify that both http://0.0.0.0:0 and https://0.0.0.0:0 can be listened to; done means both endpoints bind successfully.

Written by the indexing model from the issue text.