### Godot version

4.0.beta10.mono.official

### System information

Windows 11

### Issue description

After registering a C# Script with Autoload and trying to connect to a signal using the `Signal.connect` method (`Singleton.Signal.connect(xxx)`) fails with `Invalid get index 'Signal' (on base: 'Node (Singleton.cs)'). But with `Object.connect` it works.

### Steps to reproduce

- Create a C# class script with a Signal named `Signal` (could be any other).
- Register it with Autoload with the name `Singleton` (could be any other).
- Create a GDScript script and try to connect the Singleton's signal using `Singleton.Signal.connect(xxx)`
- When running the project it fails with `Invalid get index 'Sample' (on base: 'Node (Singleton.cs)').`

### Minimal reproduction project

[example.zip](https://github.com/godotengine/godot/files/10414500/example.zip)

ERR_FAIL_NULL_V(arg_type, ERR_BUG); 
			im_unique_sig += ",";
			im_unique_sig += get_arg_unique_sig(*arg_type);
		}
		
		String icall_method = ICALL_PREFIX;
		icall_method += itos(imethod.arguments.size());
		icall_method += "_";
		icall_method += itos(method_icalls.size());
		InternalCall im_icall = InternalCall(p_itype.api_type, icall_method, im_unique_sig);
		im_icall.is_vararg = imethod.is_vararg;
		im_icall.is_static = imethod.is_static;
		im_icall.return_type = imethod.return_type;
		for (const List<ArgumentInterface>::Element *F = imethod.arguments.front(); F; F = F->next()) {
			im_icall.argument_types.push_back(F->get().type);
		}
		List<InternalCall>::Element *match = method_icalls.find(im_icall);
		if (match) {
			if (p_itype.api_type != ClassDB::API_EDITOR) {
				match->get().editor_only = false;
			}
			method_icalls_map.insert(&imethod, &match->get());
		} else {
			List<InternalCall>::Element *added = method_icalls.push_back(im_icall);
			method_icalls_map.insert(&imethod, &added->get());
		}
	}
	return OK;
}
void BindingsGenerator::_generate_array_extensions(StringBuilder &p_output) {