### Godot version

v4.1.dev.custom_build.a7276f1ce

### System information

Win10, AMD 2600, GeForce GTX 1060, Vulkan API 1.3.205

### Issue description

I can't get correct color data from an array of source_color type.
The color data is saved as **Color** in the file:
`shader_parameter/palette = [Color (1, 0, 0, 1), Color (0, 1, 0, 1), Color (0, 0, 1, 1)]`
Shouldn't it be saved as PackedColorArray?


### Steps to reproduce

1.Declare an array of source_color type.
2.Set colors.

### Minimal reproduction project

[shadertest.zip](https://github.com/godotengine/godot/files/11246504/shadertest.zip)

if (current_function == varying_function_names.vertex) {
				if (p_varying.type < TYPE_INT) {
					*r_message = vformat(RTR("Varying with '%s' data type may only be assigned in the 'fragment' function."), get_datatype_name(p_varying.type));
					return false;
				}
				p_varying.stage = ShaderNode::Varying::STAGE_VERTEX;
			} else if (current_function == varying_function_names.fragment) {
				p_varying.stage = ShaderNode::Varying::STAGE_FRAGMENT;
			}
			break;
		case ShaderNode::Varying::STAGE_VERTEX_TO_FRAGMENT_LIGHT:
		case ShaderNode::Varying::STAGE_VERTEX:
			if (current_function == varying_function_names.fragment) {
				*r_message = RTR("Varyings which assigned in 'vertex' function may not be reassigned in 'fragment' or 'light'.");
				return false;
			}
			break;
		case ShaderNode::Varying::STAGE_FRAGMENT_TO_LIGHT:
		case ShaderNode::Varying::STAGE_FRAGMENT:
			if (current_function == varying_function_names.vertex) {
				*r_message = RTR("Varyings which assigned in 'fragment' function may not be reassigned in 'vertex' or 'light'.");
				return false;
			}
			break;
		default:
			break;
	}
	return true;
}
bool ShaderLanguage::_check_node_constness(const Node *p_node) const {