### 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 += "	MODELVIEW_MATRIX = VIEW_MATRIX * mat4(INV_VIEW_MATRIX[0], INV_VIEW_MATRIX[1], INV_VIEW_MATRIX[2], MODEL_MATRIX[3]);\n";
			if (flags[FLAG_BILLBOARD_KEEP_SCALE]) {
				code += "	MODELVIEW_MATRIX = MODELVIEW_MATRIX * mat4(vec4(length(MODEL_MATRIX[0].xyz), 0.0, 0.0, 0.0), vec4(0.0, length(MODEL_MATRIX[1].xyz), 0.0, 0.0), vec4(0.0, 0.0, length(MODEL_MATRIX[2].xyz), 0.0), vec4(0.0, 0.0, 0.0, 1.0));\n";
			}
			code += "	MODELVIEW_NORMAL_MATRIX = mat3(MODELVIEW_MATRIX);\n";
		} break;
		case BILLBOARD_FIXED_Y: {
			code += "	MODELVIEW_MATRIX = VIEW_MATRIX * mat4(vec4(normalize(cross(vec3(0.0, 1.0, 0.0), INV_VIEW_MATRIX[2].xyz)), 0.0), vec4(0.0, 1.0, 0.0, 0.0), vec4(normalize(cross(INV_VIEW_MATRIX[0].xyz, vec3(0.0, 1.0, 0.0))), 0.0), MODEL_MATRIX[3]);\n";
			if (flags[FLAG_BILLBOARD_KEEP_SCALE]) {
				code += "	MODELVIEW_MATRIX = MODELVIEW_MATRIX * mat4(vec4(length(MODEL_MATRIX[0].xyz), 0.0, 0.0, 0.0),vec4(0.0, length(MODEL_MATRIX[1].xyz), 0.0, 0.0), vec4(0.0, 0.0, length(MODEL_MATRIX[2].xyz), 0.0), vec4(0.0, 0.0, 0.0, 1.0));\n";
			}
			code += "	MODELVIEW_NORMAL_MATRIX = mat3(MODELVIEW_MATRIX);\n";
		} break;
		case BILLBOARD_PARTICLES: {
			
			code += "	mat4 mat_world = mat4(normalize(INV_VIEW_MATRIX[0]), normalize(INV_VIEW_MATRIX[1]) ,normalize(INV_VIEW_MATRIX[2]), MODEL_MATRIX[3]);\n";
			
			code += "	mat_world = mat_world * mat4(vec4(cos(INSTANCE_CUSTOM.x), -sin(INSTANCE_CUSTOM.x), 0.0, 0.0), vec4(sin(INSTANCE_CUSTOM.x), cos(INSTANCE_CUSTOM.x), 0.0, 0.0), vec4(0.0, 0.0, 1.0, 0.0), vec4(0.0, 0.0, 0.0, 1.0));\n";
			
			code += "	MODELVIEW_MATRIX = VIEW_MATRIX * mat_world;\n";
			if (flags[FLAG_BILLBOARD_KEEP_SCALE]) {
				code += "	MODELVIEW_MATRIX = MODELVIEW_MATRIX * mat4(vec4(length(MODEL_MATRIX[0].xyz), 0.0, 0.0, 0.0),vec4(0.0, length(MODEL_MATRIX[1].xyz), 0.0, 0.0), vec4(0.0, 0.0, length(MODEL_MATRIX[2].xyz), 0.0), vec4(0.0, 0.0, 0.0, 1.0));\n";
			}
			
			code += "	MODELVIEW_NORMAL_MATRIX = mat3(MODELVIEW_MATRIX);\n";
			
			code += "	float h_frames = float(particles_anim_h_frames);\n";
			code += "	float v_frames = float(particles_anim_v_frames);\n";
			code += "	float particle_total_frames = float(particles_anim_h_frames * particles_anim_v_frames);\n";
			code += "	float particle_frame = floor(INSTANCE_CUSTOM.z * float(particle_total_frames));\n";