### 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)

GDScriptParser::DataType enum_type;
				enum_type.type_source = GDScriptParser::DataType::ANNOTATED_EXPLICIT;
				enum_type.kind = GDScriptParser::DataType::ENUM;
				enum_type.builtin_type = Variant::DICTIONARY;
				enum_type.enum_type = member.m_enum->identifier->name;
				enum_type.native_type = p_class->fqcn + "." + member.m_enum->identifier->name;
				enum_type.is_meta_type = true;
				enum_type.is_constant = true;
				const GDScriptParser::EnumNode *prev_enum = current_enum;
				current_enum = member.m_enum;
				Dictionary dictionary;
				for (int j = 0; j < member.m_enum->values.size(); j++) {
					GDScriptParser::EnumNode::Value &element = member.m_enum->values.write[j];
					if (element.custom_value) {
						reduce_expression(element.custom_value);
						if (!element.custom_value->is_constant) {
							push_error(R"(Enum values must be constant.)", element.custom_value);
						} else if (element.custom_value->reduced_value.get_type() != Variant::INT) {
							push_error(R"(Enum values must be integers.)", element.custom_value);
						} else {
							element.value = element.custom_value->reduced_value;
							element.resolved = true;
						}
					} else {
						if (element.index > 0) {
							element.value = element.parent_enum->values[element.index - 1].value + 1;
						} else {
							element.value = 0;
						}
						element.resolved = true;