### Godot version

4.0.3

### System information

Win7

### Issue description

![image](https://github.com/godotengine/godot/assets/28286958/abec9d3c-e078-424c-9430-d9fe8897aad6)


### Steps to reproduce

1. Create shader
2. Add uint with hex, e.g. 0xffffu

### Minimal reproduction project

N/A
switch (p_op) {
		case OP_ASSIGN:
		case OP_ASSIGN_ADD:
		case OP_ASSIGN_SUB:
		case OP_ASSIGN_MUL:
		case OP_ASSIGN_DIV:
		case OP_ASSIGN_MOD:
		case OP_ASSIGN_SHIFT_LEFT:
		case OP_ASSIGN_SHIFT_RIGHT:
		case OP_ASSIGN_BIT_AND:
		case OP_ASSIGN_BIT_OR:
		case OP_ASSIGN_BIT_XOR:
			return true;
		default:
			return false;
	}
}
bool ShaderLanguage::_validate_varying_assign(ShaderNode::Varying &p_varying, String *r_message) {
	if (current_function != "vertex" && current_function != "fragment") {
		*r_message = vformat(RTR("Varying may not be assigned in the '%s' function."), current_function);
		return false;
	}
	switch (p_varying.stage) {
		case ShaderNode::Varying::STAGE_UNKNOWN: