### 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)

case TEXTURE_CHANNEL_BLUE: {
				code += "	vec4 roughness_texture_channel = vec4(0.0,0.0,1.0,0.0);\n";
			} break;
			case TEXTURE_CHANNEL_ALPHA: {
				code += "	vec4 roughness_texture_channel = vec4(0.0,0.0,0.0,1.0);\n";
			} break;
			case TEXTURE_CHANNEL_GRAYSCALE: {
				code += "	vec4 roughness_texture_channel = vec4(0.333333,0.333333,0.333333,0.0);\n";
			} break;
			case TEXTURE_CHANNEL_MAX:
				break; 
		}
		if (flags[FLAG_UV1_USE_TRIPLANAR]) {
			code += "	float roughness_tex = dot(triplanar_texture(texture_roughness,uv1_power_normal,uv1_triplanar_pos),roughness_texture_channel);\n";
		} else {
			code += "	float roughness_tex = dot(texture(texture_roughness,base_uv),roughness_texture_channel);\n";
		}
		code += "	ROUGHNESS = roughness_tex * roughness;\n";
		code += "	SPECULAR = specular;\n";
	} else {
		if (flags[FLAG_UV1_USE_TRIPLANAR]) {
			code += "	vec4 orm_tex = triplanar_texture(texture_orm,uv1_power_normal,uv1_triplanar_pos);\n";
		} else {
			code += "	vec4 orm_tex = texture(texture_orm,base_uv);\n";
		}
		code += "	ROUGHNESS = orm_tex.g;\n";
		code += "	METALLIC = orm_tex.b;\n";
	}
	if (features[FEATURE_NORMAL_MAPPING]) {
		if (flags[FLAG_UV1_USE_TRIPLANAR]) {