### Godot version

4.0 Beta10

### System information

Windows 10, Vulkan, GTX1060

### Issue description

`PropertyTweener`'s methods' return value are not discarded and effect the unary operator at next line.

In Editor:
![in_editor](https://user-images.githubusercontent.com/61624558/210715100-04bdf283-7954-4be3-94ca-338987b24c5b.png)


In cpp:
![in_cpp](https://user-images.githubusercontent.com/61624558/210715127-519f6d54-fc15-468f-9aca-ba7d387a5a7b.png)


### Steps to reproduce

Just run the Minimal reproduction project.

### Minimal reproduction project

[Bug Report.zip](https://github.com/godotengine/godot/files/10349829/Bug.Report.zip)

result.kind = GDScriptParser::DataType::NATIVE;
		Object *obj = p_value;
		if (!obj) {
			return GDScriptParser::DataType();
		}
		result.native_type = obj->get_class_name();
		Ref<Script> scr = p_value; 
		if (scr.is_valid()) {
			result.is_meta_type = true;
		} else {
			result.is_meta_type = false;
			scr = obj->get_script();
		}
		if (scr.is_valid()) {
			Ref<GDScript> gds = scr;
			if (gds.is_valid()) {
				
				
				String script_path = gds->get_script_path();
				Ref<GDScriptParserRef> ref = get_parser_for(script_path);
				if (ref.is_null()) {
					push_error(vformat(R"(Could not find script "%s".)", script_path), p_source);
					GDScriptParser::DataType error_type;
					error_type.kind = GDScriptParser::DataType::VARIANT;
					return error_type;
				}
				Error err = ref->raise_status(GDScriptParserRef::INHERITANCE_SOLVED);
				GDScriptParser::ClassNode *found = nullptr;
				if (err == OK) {
					found = ref->get_parser()->find_class(gds->fully_qualified_name);