### 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 (tk.type != TK_SEMICOLON) {
						_set_expected_error(";");
						return ERR_PARSE_ERROR;
					}
#ifdef DEBUG_ENABLED
					keyword_completion_context = CF_GLOBAL_SPACE;
#endif 
					completion_type = COMPLETION_NONE;
					current_uniform_hint = ShaderNode::Uniform::HINT_NONE;
					current_uniform_filter = FILTER_DEFAULT;
					current_uniform_repeat = REPEAT_DEFAULT;
					current_uniform_instance_index_defined = false;
				} else { 
					ShaderNode::Varying varying;
					varying.type = type;
					varying.precision = precision;
					varying.interpolation = interpolation;
					varying.tkpos = prev_pos;
					varying.array_size = array_size;
					tk = _get_token();
					if (tk.type != TK_SEMICOLON && tk.type != TK_BRACKET_OPEN) {
						if (array_size == 0) {
							_set_expected_error(";", "[");
						} else {
							_set_expected_error(";");
						}
						return ERR_PARSE_ERROR;
					}
					if (tk.type == TK_BRACKET_OPEN) {
						Error error = _parse_array_size(nullptr, constants, true, nullptr, &varying.array_size, nullptr);