### Godot version

v4.0.beta.custom_build [1d14c054a]

### System information

Kubuntu 22.10

### Issue description

Regression in master (in beta 10 the following script works correctly).

### Steps to reproduce

```gdscript
@tool
extends EditorScript

func wait(time: float) -> void:
    await get_editor_interface().get_tree().create_timer(time).timeout

func _run() -> void:
    reference()
    # Error: Cannot get return value of call to "wait()" because it returns "void".
    await wait(1.0)
    print("Test")
    unreference()
```

### Minimal reproduction project

N/A
int i = 0;
			for (const GDScriptParser::DataType &par_type : parameters_types) {
				valid = valid && par_type == p_function->parameters[i++]->get_datatype();
			}
			if (!valid) {
				
				String parent_signature = function_name.operator String() + "(";
				int j = 0;
				for (const GDScriptParser::DataType &par_type : parameters_types) {
					if (j > 0) {
						parent_signature += ", ";
					}
					String parameter = par_type.to_string();
					if (parameter == "null") {
						parameter = "Variant";
					}
					parent_signature += parameter;
					if (j == parameters_types.size() - default_par_count) {
						parent_signature += " = default";
					}
					j++;
				}
				parent_signature += ") -> ";
				const String return_type = parent_return_type.is_hard_type() ? parent_return_type.to_string() : "Variant";
				if (return_type == "null") {
					parent_signature += "void";
				} else {
					parent_signature += return_type;
				}
				push_error(vformat(R"(The function signature doesn't match the parent. Parent signature is "%s".)", parent_signature), p_function);