feature: Map host.docker.internal into the container

[Bilge]

To make it easy to access host services, map host.docker.internal to host-gateway at container creation time. host-gateway is a special name that Docker understands at container creation time, but cannot be accessed at runtime. Mapping it to the canonical host.docker.internal allows other application to work out-of-the-box with the assumption this address will be available at runtime.