### 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)

return err;
					}
				}
			}
		}
	}
	{
		
		Error err = OK;
		_parse_function(err, p_script, p_class, nullptr);
		if (err) {
			return err;
		}
	}
	if (p_class->onready_used) {
		
		Error err = OK;
		_parse_function(err, p_script, p_class, nullptr, true);
		if (err) {
			return err;
		}
	}
#ifdef DEBUG_ENABLED
	
	if (p_keep_state) {
		for (RBSet<Object *>::Element *E = p_script->instances.front(); E;) {
			RBSet<Object *>::Element *N = E->next();
			ScriptInstance *si = E->get()->get_script_instance();
			if (si->is_placeholder()) {
#ifdef TOOLS_ENABLED