### Godot version

4.0 beta 10

### System information

Windows 10

### Issue description

Godot crashes when i accidently name 2 items in an enum the same

EDIT:
The editor freeze for some seconds, then both editor- and console-window dissapear

### Steps to reproduce

Write

```gdscript
enum {
    A,
}
```

and then add a second line with another A:

```gdscript
enum {
    A,
    A # <- crash
}
```

Does not always immediatly happen if i copy&paste items.
Does not happen when i change the script in another editor and open the script in Godot.

### Minimal reproduction project

[enum.zip](https://github.com/godotengine/godot/files/10313759/enum.zip)

reduce_expression(p_unary_op->operand);
	GDScriptParser::DataType result;
	if (p_unary_op->operand == nullptr) {
		result.kind = GDScriptParser::DataType::VARIANT;
		p_unary_op->set_datatype(result);
		return;
	}
	GDScriptParser::DataType operand_type = p_unary_op->operand->get_datatype();
	if (p_unary_op->operand->is_constant) {
		p_unary_op->is_constant = true;
		p_unary_op->reduced_value = Variant::evaluate(p_unary_op->variant_op, p_unary_op->operand->reduced_value, Variant());
		result = type_from_variant(p_unary_op->reduced_value, p_unary_op);
	}
	if (operand_type.is_variant()) {
		result.kind = GDScriptParser::DataType::VARIANT;
		mark_node_unsafe(p_unary_op);
	} else {
		bool valid = false;
		result = get_operation_type(p_unary_op->variant_op, operand_type, valid, p_unary_op);
		if (!valid) {
			push_error(vformat(R"(Invalid operand of type "%s" for unary operator "%s".)", operand_type.to_string(), Variant::get_operator_name(p_unary_op->variant_op)), p_unary_op);
		}
	}
	p_unary_op->set_datatype(result);
}
void GDScriptAnalyzer::const_fold_array(GDScriptParser::ArrayNode *p_array, bool p_is_const) {