### 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)

ADD_PROPERTYI(PropertyInfo(Variant::BOOL, "use_point_size"), "set_flag", "get_flag", FLAG_USE_POINT_SIZE);
	ADD_PROPERTY(PropertyInfo(Variant::FLOAT, "point_size", PROPERTY_HINT_RANGE, "0.1,128,0.1,suffix:px"), "set_point_size", "get_point_size");
	ADD_PROPERTYI(PropertyInfo(Variant::BOOL, "use_particle_trails"), "set_flag", "get_flag", FLAG_PARTICLE_TRAILS_MODE);
	ADD_GROUP("Proximity Fade", "proximity_fade_");
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "proximity_fade_enabled"), "set_proximity_fade_enabled", "is_proximity_fade_enabled");
	ADD_PROPERTY(PropertyInfo(Variant::FLOAT, "proximity_fade_distance", PROPERTY_HINT_RANGE, "0,4096,0.01,suffix:m"), "set_proximity_fade_distance", "get_proximity_fade_distance");
	ADD_GROUP("MSDF", "msdf_");
	ADD_PROPERTY(PropertyInfo(Variant::FLOAT, "msdf_pixel_range", PROPERTY_HINT_RANGE, "1,100,1"), "set_msdf_pixel_range", "get_msdf_pixel_range");
	ADD_PROPERTY(PropertyInfo(Variant::FLOAT, "msdf_outline_size", PROPERTY_HINT_RANGE, "1,250,1"), "set_msdf_outline_size", "get_msdf_outline_size");
	ADD_GROUP("Distance Fade", "distance_fade_");
	ADD_PROPERTY(PropertyInfo(Variant::INT, "distance_fade_mode", PROPERTY_HINT_ENUM, "Disabled,PixelAlpha,PixelDither,ObjectDither"), "set_distance_fade", "get_distance_fade");
	ADD_PROPERTY(PropertyInfo(Variant::FLOAT, "distance_fade_min_distance", PROPERTY_HINT_RANGE, "0,4096,0.01,suffix:m"), "set_distance_fade_min_distance", "get_distance_fade_min_distance");
	ADD_PROPERTY(PropertyInfo(Variant::FLOAT, "distance_fade_max_distance", PROPERTY_HINT_RANGE, "0,4096,0.01,suffix:m"), "set_distance_fade_max_distance", "get_distance_fade_max_distance");
	BIND_ENUM_CONSTANT(TEXTURE_ALBEDO);
	BIND_ENUM_CONSTANT(TEXTURE_METALLIC);
	BIND_ENUM_CONSTANT(TEXTURE_ROUGHNESS);
	BIND_ENUM_CONSTANT(TEXTURE_EMISSION);
	BIND_ENUM_CONSTANT(TEXTURE_NORMAL);
	BIND_ENUM_CONSTANT(TEXTURE_RIM);
	BIND_ENUM_CONSTANT(TEXTURE_CLEARCOAT);
	BIND_ENUM_CONSTANT(TEXTURE_FLOWMAP);
	BIND_ENUM_CONSTANT(TEXTURE_AMBIENT_OCCLUSION);
	BIND_ENUM_CONSTANT(TEXTURE_HEIGHTMAP);
	BIND_ENUM_CONSTANT(TEXTURE_SUBSURFACE_SCATTERING);
	BIND_ENUM_CONSTANT(TEXTURE_SUBSURFACE_TRANSMITTANCE);
	BIND_ENUM_CONSTANT(TEXTURE_BACKLIGHT);
	BIND_ENUM_CONSTANT(TEXTURE_REFRACTION);
	BIND_ENUM_CONSTANT(TEXTURE_DETAIL_MASK);
	BIND_ENUM_CONSTANT(TEXTURE_DETAIL_ALBEDO);
	BIND_ENUM_CONSTANT(TEXTURE_DETAIL_NORMAL);