Use Proxy::HttpRequest in Proxy::ContainerGateway::ForemanApi

[ekohl]

Proxy::ContainerGateway::ForemanApi looks a lot like what Proxy::HttpRequest does. That also has the benefit that it offers client certificates which can be used to authenticate requests server side. It also sets the correct CA to verify requests without relying on them in the system store.

[ianballou]

I'm not using Proxy::HttpRequest directly, but this was essentially fixed here: #10