Host header not arriving correctly

[CherryDT]

Describe the bug
Host header (which should be some-domain.loophole.site) gets overridden with 127.0.0.1:<port>.

To Reproduce
Steps to reproduce the behavior:

1. Create a server that logs the Host header it receives
2. Navigate to the loopholed domain
3. Note that the host header shows up as 127.0.0.1:3000 and not my-test.loophole.site

Expected behavior
Host header should not be changed. Alternatively (perhaps even better), there should be a way to set which host header should be used. But hardcoding to 127.0.0.1:<port> does not make sense.

Notes
I think this was introduced with #172 but I don't understand why, it breaks a lot of functionality. The idea seems to have originally come from #152 but the original request asked for some --override-host argument to specify it manually, like I also suggested above, which would have been fine, however it was hardcoded instead.