### 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)

code += "		float d = msdf_median(albedo_tex.r, albedo_tex.g, albedo_tex.b, albedo_tex.a) - 0.5;\n";
		code += "		if (msdf_outline_size > 0.0) {\n";
		code += "			float cr = clamp(msdf_outline_size, 0.0, msdf_pixel_range / 2.0) / msdf_pixel_range;\n";
		code += "			albedo_tex.a = clamp((d + cr) * px_size, 0.0, 1.0);\n";
		code += "		} else {\n";
		code += "			albedo_tex.a = clamp(d * px_size + 0.5, 0.0, 1.0);\n";
		code += "		}\n";
		code += "		albedo_tex.rgb = vec3(1.0);\n";
		code += "	}\n";
	} else if (flags[FLAG_ALBEDO_TEXTURE_FORCE_SRGB]) {
		code += "	albedo_tex.rgb = mix(pow((albedo_tex.rgb + vec3(0.055)) * (1.0 / (1.0 + 0.055)),vec3(2.4)),albedo_tex.rgb.rgb * (1.0 / 12.92),lessThan(albedo_tex.rgb,vec3(0.04045)));\n";
	}
	if (flags[FLAG_ALBEDO_FROM_VERTEX_COLOR]) {
		code += "	albedo_tex *= COLOR;\n";
	}
	code += "	ALBEDO = albedo.rgb * albedo_tex.rgb;\n";
	if (!orm) {
		if (flags[FLAG_UV1_USE_TRIPLANAR]) {
			code += "	float metallic_tex = dot(triplanar_texture(texture_metallic,uv1_power_normal,uv1_triplanar_pos),metallic_texture_channel);\n";
		} else {
			code += "	float metallic_tex = dot(texture(texture_metallic,base_uv),metallic_texture_channel);\n";
		}
		code += "	METALLIC = metallic_tex * metallic;\n";
		switch (roughness_texture_channel) {
			case TEXTURE_CHANNEL_RED: {
				code += "	vec4 roughness_texture_channel = vec4(1.0,0.0,0.0,0.0);\n";
			} break;
			case TEXTURE_CHANNEL_GREEN: {
				code += "	vec4 roughness_texture_channel = vec4(0.0,1.0,0.0,0.0);\n";
			} break;