[Cake.Frosting] has exit code -1 for any kind of error

### Prerequisites

- [X] I have written a descriptive issue title
- [X] I have searched [issues](https://github.com/cake-build/cake/issues) to ensure it has not already been reported

### Cake runner

Cake Frosting, Cake runner for .NET Core

### Cake version

2.0.0

### Operating system

Linux, Windows

### Operating system architecture

64-Bit

### CI Server

gitlab

### What are you seeing?

exit code is -1

### What is expected?

exit code is > 0 for errors

### Steps to Reproduce

simple frosting project
```
public static class Program
{
class MyCtx : FrostingContext
{
public MyCtx(ICakeContext context) : base(context)
{
}
}
public static int Main(string[] args)
{
return new CakeHost()
.UseContext()
.Run(args);
}
}
```

- call with `dotnet run -- --target foobar`
- exit code is -1

### Output log

_No response_

Reproduce the issue with a simple Cake Frosting project using `dotnet run -- --target foobar`, then trace the `CakeHost.Run` entry point and how it converts errors into a process exit code. Done means an invalid target or other error returns a positive exit code on Linux and Windows.

Written by the indexing model from the issue text.