[Bug]: Refit interfaces do not implement base interface non refit methods

[TimothyMakkison]

Describe the bug 🐞

Generated refit interfaces are invalid if the base interface has a non refit method.

Step to reproduce

// 'Generated.IGeneratedInterface' does not implement interface member 'IBaseInterface.NonRefitMethod()'
var gitHubApi = RestService.For<IGeneratedInterface>("https://api.github.com");

public interface IGeneratedInterface : IBaseInterface
{
    [Get("/users")]
    Task<string> Get();
}

public interface IBaseInterface
{
    void NonRefitMethod();
}

Reproduction repository

https://github.com/reactiveui/refit

Expected behavior

Refit should generate stub implementations which throw an error when called to satisfy the interface. Similar to how non refit methods are handled in non derived refit interfaces.

IDE

Rider Windows

[TimothyMakkison]

Related #1687