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# What does this PR do?

In title. Adds argument `--hostname` in router to support something like
`--hostname ::`. Tested with

```commandline
cargo run -- --port 8080 --hostname ::
curl -I -X GET 'http://[::1]:8080/health

'  # failed before this commit
```

Trigger CI

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Co-authored-by: Phil Chen <philchen2000@gmail.com>