closes#11766, refs 7284227f1
- when we changed from host to hostname, more changed than just using the x-forwarded-host if trusted because express req.hostname does not return the port
- this causes issues with an infinite redirect if you try to set a different admin host with a port
- added a test to demonstrate the case, that didn't fail due to an error in the test logic
- switched from redirecting based on req.hostname to using req.vhost.host which has the correct trusted, requested value that we should rely on
- simplified the comparison logic to explicitly compare host with host
4a67ea5546