### 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
append(p_source);
			append(idx);
		} break;
		default: {
			ERR_PRINT("Compiler bug: unresolved assign.");
			
			append_opcode(GDScriptFunction::OPCODE_ASSIGN);
			append(p_target);
			append(p_source);
		}
	}
}
void GDScriptByteCodeGenerator::write_assign(const Address &p_target, const Address &p_source) {
	if (p_target.type.kind == GDScriptDataType::BUILTIN && p_target.type.builtin_type == Variant::ARRAY && p_target.type.has_container_element_type()) {
		append_opcode(GDScriptFunction::OPCODE_ASSIGN_TYPED_ARRAY);
		append(p_target);
		append(p_source);
	} else if (p_target.type.kind == GDScriptDataType::BUILTIN && p_source.type.kind == GDScriptDataType::BUILTIN && p_target.type.builtin_type != p_source.type.builtin_type) {
		
		append_opcode(GDScriptFunction::OPCODE_ASSIGN_TYPED_BUILTIN);
		append(p_target);
		append(p_source);
		append(p_target.type.builtin_type);
	} else {
		append_opcode(GDScriptFunction::OPCODE_ASSIGN);
		append(p_target);
		append(p_source);
	}
}
void GDScriptByteCodeGenerator::write_assign_true(const Address &p_target) {