### 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 (!is_struct && !is_token_datatype(tk.type)) {
						_set_error(RTR("Expected a valid data type for argument."));
						return ERR_PARSE_ERROR;
					}
					if (param_qualifier == ARGUMENT_QUALIFIER_OUT || param_qualifier == ARGUMENT_QUALIFIER_INOUT) {
						if (is_sampler_type(get_token_datatype(tk.type))) {
							_set_error(RTR("Opaque types cannot be output parameters."));
							return ERR_PARSE_ERROR;
						}
					}
					if (is_struct) {
						param_type = TYPE_STRUCT;
					} else {
						param_type = get_token_datatype(tk.type);
						if (param_type == TYPE_VOID) {
							_set_error(RTR("Void type not allowed as argument."));
							return ERR_PARSE_ERROR;
						}
					}
					if (param_precision != PRECISION_DEFAULT && _validate_precision(param_type, param_precision) != OK) {
						return ERR_PARSE_ERROR;
					}
#ifdef DEBUG_ENABLED
					keyword_completion_context = CF_UNSPECIFIED;
#endif 
					tk = _get_token();
					if (tk.type == TK_BRACKET_OPEN) {
						Error error = _parse_array_size(nullptr, constants, true, nullptr, &arg_array_size, nullptr);
						if (error != OK) {
							return error;