### 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 (script_class->members_indices.has(first)) {
				resolve_class_member(script_class, first, p_type);
				GDScriptParser::ClassNode::Member member = script_class->get_member(first);
				switch (member.type) {
					case GDScriptParser::ClassNode::Member::CLASS:
						result = member.get_datatype();
						break;
					case GDScriptParser::ClassNode::Member::ENUM:
						result = member.get_datatype();
						break;
					case GDScriptParser::ClassNode::Member::CONSTANT:
						if (member.get_datatype().is_meta_type) {
							result = member.get_datatype();
							result.is_meta_type = false;
							break;
						} else if (Ref<Script>(member.constant->initializer->reduced_value).is_valid()) {
							Ref<GDScript> gdscript = member.constant->initializer->reduced_value;
							if (gdscript.is_valid()) {
								Ref<GDScriptParserRef> ref = get_parser_for(gdscript->get_script_path());
								if (ref->raise_status(GDScriptParserRef::INHERITANCE_SOLVED) != OK) {
									push_error(vformat(R"(Could not parse script from "%s".)", gdscript->get_script_path()), p_type);
									return bad_type;
								}
								result = ref->get_parser()->head->get_datatype();
								result.is_meta_type = false;
							} else {
								Ref<Script> script = member.constant->initializer->reduced_value;
								result.kind = GDScriptParser::DataType::SCRIPT;
								result.builtin_type = Variant::OBJECT;