### 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)

if (p_source.kind == GDScriptParser::DataType::BUILTIN && p_source.builtin_type == Variant::NIL) {
		
		return true;
	}
	StringName src_native;
	Ref<Script> src_script;
	const GDScriptParser::ClassNode *src_class = nullptr;
	switch (p_source.kind) {
		case GDScriptParser::DataType::NATIVE:
			if (p_target.kind != GDScriptParser::DataType::NATIVE) {
				
				return false;
			}
			if (p_source.is_meta_type) {
				src_native = GDScriptNativeClass::get_class_static();
			} else {
				src_native = p_source.native_type;
			}
			break;
		case GDScriptParser::DataType::SCRIPT:
			if (p_target.kind == GDScriptParser::DataType::CLASS) {
				
				return false;
			}
			if (p_source.is_meta_type) {
				src_native = p_source.script_type->get_class_name();
			} else {
				src_script = p_source.script_type;
				src_native = src_script->get_instance_base_type();
			}