### 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)

_set_tkpos(prev_pos);
				_get_completable_identifier(nullptr, COMPLETION_MAIN_FUNCTION, name);
				if (name == StringName()) {
					if (is_constant) {
						_set_error(RTR("Expected an identifier or '[' after type."));
					} else {
						_set_error(RTR("Expected a function name after type."));
					}
					return ERR_PARSE_ERROR;
				}
				if (shader->structs.has(name) || _find_identifier(nullptr, false, constants, name) || has_builtin(p_functions, name)) {
					_set_redefinition_error(String(name));
					return ERR_PARSE_ERROR;
				}
				tk = _get_token();
				if (tk.type != TK_PARENTHESIS_OPEN) {
					if (type == TYPE_VOID) {
						_set_error(RTR("Expected '(' after function identifier."));
						return ERR_PARSE_ERROR;
					}
					
					while (true) {
						ShaderNode::Constant constant;
						constant.name = name;
						constant.type = is_struct ? TYPE_STRUCT : type;
						constant.type_str = struct_name;
						constant.precision = precision;
						constant.initializer = nullptr;
						constant.array_size = array_size;
						is_const_decl = true;