Treat .NET 7 `required` properties as actually required by default

**Code snippet:**
```cs
public class Options
{
[Option]
public required int Port { get; init; }

[Option]
public required string Server { get; init; }
}
```

**Expected behaviour:** Both `Port` and `Server` are required and the parsing fails if at least on of them is not present.

**Actual behaviour:** They are not required, I still have to specify `[Option(Required = true)]` in order for it to work